Orchard Outlook Newsletter Vol. 26, No 15

Thursday, August 13, 2026

Today's newsletter focuses on the final stretch of the growing season, with reminders about late-season diseases, apple maggot, and management practices that can influence fruit quality at harvest and in storage. With fruit sizing and adding weight to the support system, now is also an excellent time to take steps to protect trees and trellis from the risk of wind damage. Plus, don't miss highlights from the recent NSFGA Summer Orchard Tour, where growers shared innovative approaches to irrigation, soil health, and orchard efficiency.

Please note that the industry-wide Honeycrisp fruit maturity assessments will be slightly delayed this year due to a personal commitment. I anticipate beginning assessments around August 31 and appreciate your understanding.


Table of Contents:


Weather
  • Degree Day Accumulations
  • Precipitation Update
  • Preharvest Management of Apple Storage Rots and Fungi
Insects
  • Apple maggot
Horticulture
  • Tree Health
  • Cover Crops
  • On Farm Nursery
  • Preharvest Management Strategies - ReTain and Harvista
  • Summer Pruning and Hedging
  • Reflective Mulch
  • Estimating Bin Requirements
  • Using a Delta Absorbance (DA) Meter
  • Reducing bruising
  • Considering watercore
  • Avoiding internal browning

Events and Notices

  • NSFGA Summer Tour Digest - August 5, 2026

Weather


Degree Day Accumulations

Harrison Wright shared that as of August 4, the growing degree days remain close to the 10-year average, but below the 5-year average (with the previous 5 years being some of the hottest growing seasons on record). 

Harvest dates are difficult to predict based on degree day accumulations alone. Use harvest dates from similar years as estimates and leave a comfortable buffer for preharvest intervals with fungicides and insecticides. 


Figure 1: Heating degree day accumulations for plant (above 5°C) and insect (above 10°C) development from March 1 to August 4 for the past 17 seasons. Provided by Harrison Wright (AAFC).


Precipitation Update

We are continuing our sawtooth pattern of alternatively being either well above or well below the precipitation monthly averages. Harrison Wright shared that July was above average after a dry June. The July total was mostly a result of a few storms in the last two weeks of the month. Certainly a welcome amount of rain!

Figure 2: Monthly precipitation totals in 2026 (triangles) compared with the 25-year average (bar graphs). Provided by Harrison Wright (AAFC Plant Physiology).





Late Season Diseases


Preharvest Management of Apple Storage Rots and Fungi

A well-timed preharvest chemical control can go a long way to prevent storage rots (although it will not make up for lack of earlier protection). Pinpoint scab, black rot, flyspeck, sooty blotch and brooks spot are preharvest issues that infect fruit in the orchard. Fungal spores that land on unprotected fruit can germinate and show up as infections in storage. Preharvest fungicide is your only protection going into storage.

Recommendations:

  • Note the risk of summer diseases if spray programs are stretched to the limit. Once the 10-day interval has been reached, it is better to re-apply fungicide protection prior to rainfall or possible infection rather than after. 
  • Late season fungicide treatment is highly recommended in blocks that have leaf and/or fruit scab. Pay special attention to the tops of tall trees that might not have had adequate fungicide coverage. Ambrosia trees in particular are very susceptible to scab and the fruit are stored for a long period of time.
  • The group 7 & 11 products Pristine and Merivon can be applied up to 5 days before harvest (and preferably within 2 weeks). They are labelled for the control of scab, black rot, flyspeck, and sooty blotch. The short PHI and good activity are especially helpful for protecting apples being placed in long-term storage.
  • Don't put away the sprayer too early! Late varieties benefit from a preharvest spray too. Also, cumulative rainfall of 25-50 mm washes off fungicide protection. Growers who stop their fungicide program early see early symptoms of diseases in storage.
  • However, be very aware of fungicide preharvest intervals. Plan for an early harvest when considering chemical PHIs.
  • Of course, avoid bruising or wounding to prevent infections of blue and gray moulds. Take the time to educate staff on the proper way to handle fruit.


Insects


Apple Maggot

  • Clean maggot traps 7 to 10 days after treating a block for maggot and monitor for new trap captures. Retreat if new maggot flies are caught. Flies emerge over a period of time so for satisfactory maggot control, monitor the presence of apple maggot flies to inform treatment programs. Remember, a single female can lay hundreds of eggs so do not stop treatment prematurely.
  • Re-treatment is required every 10-14 days under pressure or cumulative rainfall of 12.5 to 25 mm (0.5 to 1 inch). Danitol and products registered for suppression are expected to have a relatively shorter field residual life of 7 to 10 days. Insecticide residue should be maintained through to the end of August.
  • Apple maggot flies are weak flyers so a border/perimeter spray of Imidan near known hotspots may be an approach to help kill adult flies from the source. (Being cognizant of the 22-day PHI and REI restrictions).
  • In organic orchards, Surround can be used to deter egg laying and GF 120 fruit fly bait can be used for suppression of adult flies.
  • Apple maggots pupate in the soil and may not emerge until up to four years later. Therefore, several years of diligent management are required to reduce the resident insect population.


Figure 2: An apple maggot fly on a 1 x 1 inch grid of a yellow sticky trap. The fly has a black F-shaped pattern on the wing that mimic's the shape of a spider's legs. It is slightly smaller than a common house fly and has a white dot in the middle of its back.



Horticulture



Tree Health

  • Activities to protect trees from the wind are valuable at this time of the year as trees are carrying the extra weight of fruit. 
    • Focus on fixing broken posts and checking wire tension. 
    • Check on aging systems and where posts are too far apart. Improvements for existing trellis might include in-filling posts, installing anchors on the windward side, and temporary reinforcements on the most exposed tree rows. 
  • Check the height of the graft union above the soil line. If frost heaving has occurred it is recommended that you hill soil to cover exposed roots and an overexposed rootstock shank. An overexposed rootstock shank may be more susceptible to winter injury during fluctuating warm winter temperatures. Exposed roots are also susceptible to herbicide sprays.

Cover Crops

  • Perennia has a series of videos about cover crops by Sonny Murray and Rosalie Gillis-Madden that can be accessed from our website.
  • For August and September plantings of cover crops, check out the factsheet about Fall Cover Crop Species Selection and Management that was written by Sonny Murray and Caitlin Congdon. During the summer orchard tour, Harrison Van Meekeren shared the importance of making sure the chosen cover crops winter kill if spring planting is planned.

On-Farm Nursery

  • It is highly recommended that you water your nursery before and after budding to encourage callus formation and a healthy union. 
  • Find a source of budwood that does not have a history of fire blight strikes. Trees that have shown signs of fire blight strikes or that are situated near fire blight infections should be eliminated as a source of budwood. Cut budwood fresh every morning if possible.
  • Occasionally sanitize all tools used for budwood collection, storage, and budding by washing in detergent and water and disinfecting with sodium hypochlorite bleach. During bud wood collection and budding, frequently spray hand tools with fresh sodium hypochlorite bleach solution.
    • The general recommendation is one part bleach to ten parts of water.
    • If bleach is too tough on tools, Lysol and Pinesol at one part product to ten parts of water are good alternatives. 
    • Do NOT use rubbing alcohol because even at 70% to 99% concentration it allows bacteria to survive (California Agriculture 1991).



Harvest Fruit Quality


Preharvest Management Strategies - ReTain and Harvista

  • The economic return for these products is expected to be greatest with good crop loads, high-value varieties, and good fruit quality.
  • For local rates and timing, visit our resource on ReTain and Harvista for Gala and Honeycrisp.
  • Harvista blocks ethylene action in fruit, even after ethylene has been produced by fruit so it can be applied within a few days of harvest. ReTain requires a timely application to fruit before ethylene production escalates so it is applied several weeks prior to anticipated harvest.
  • These products are not expected to prevent the structural stem damage that is associated with broken stem windfalls due to high winds.
  • A new online tool is available from Valent: ReTain PGR Apple ROI Calculator.

Summer Pruning and Hedging

Vigorous shoot growth in orchards could present a fruit shading problem. Summer pruning could be used to expose the fruit to more sunlight to improve fruit colour. Also, summer pruning controls vigour so it could divert more calcium to fruit. The practice might help reduce the risk of bitter pit. 

Recommendations:

  • Summer pruning should involve making the pruning cuts to one- and two-year old wood. Remove vigorous shoots in the entire canopy but especially at the top.
  • Leave the weaker side laterals to supply the fruit with carbohydrates. If you over prune you could end up reducing fruit size.
  • Avoid leaving short stubs as they will produce two or more shoots next spring.
  • Hedging done in August after terminal bud set is not expected to result in regrowth this season.

Reflective Mulch

Reflective mulch will help to expose more fruit surfaces to sunlight so that the fruit begins forming red colour pigments. More sunlight exposure can help to maximize red colour which in turn improves fruit quality and harvest efficiency. The reflective mulch may be applied to high-value apple varieties at 2-3 weeks before harvest.


Estimating Bin Requirements

Use the following math to help you estimate bin requirements if the fruit in a block are relatively uniform in size. The crop volume is determined by the number of trees, number of fruit, and fruit size.

To approximate the number of bins required:
  1. Calculate the number of apples per acre (# trees per acre x avg # apples per tree)
  2. Refer to table 4 for the # of apples per 17 bu bin of a selected average count size
  3. Bins/acre = # of apples per acre / # apples per bin for selected count size

Table 4: Number of apples of a selected count size to fill a 17 bu bin.

Example 1: 125 count size
  1. 1000 trees per acre x 60 apples/tree = 60,000 apples/acre
  2. There are 2125 apples per bin of 125 count size.
  3. Bins/acre = 60,000 apples per acre/2125 apples per bin = 28.2 bins/acre

Example 2: 113 count size
  1. 1000 trees per acre x 60 apples/tree = 60,000 apples/acre
  2. There are 1921 apples per bin of 113 count size.
  3. Bins/acre = 60,000 apples per acre/1921 apples per bin = 31.2 bins

Recommendations:

    • Now is a great time to consider your bin inventory, repair bins, and ensure bins are well-washed.


    Using a Delta Absorbance (DA) Meter

    The DA meter is a handheld device used to monitor the chlorophyll content of the apple peel as an indication of fruit maturity. Chlorophyll degrades as the fruit matures so the reading correlates with other changes that happen during the ripening process. 

    What you need to know:
    • Varieties have a unique set of DA meter values associated with them that are the boundaries of when to begin and end harvest, based on local research by AAFC. This means that you cannot test a Gala and expect it to match values set for Honeycrisp. McIntosh and Cortland do not work well with the DA meter.
    • DA meter values become smaller as fruit matures. Typically the readings will change by 0.1 units in one week (ex. from 0.6 to 0.5). There may be daily fluctuations so do not take daily readings as the time scale is too frequent.
    • The late Dr. John DeLong who spearheaded local research on the topic recorded a podcast with us in 2019 on 'Sensing Fruit Maturity'.
    • DA meter readings after Harvista/ReTain might not actually represent maturity. Changes to chlorophyll content caused by these products might not be synchronous with other maturity indicators. Do not rely on DA meter readings on fruit treated with ReTain or Harvista and instead use other maturity indicators.

    Using the DA meter:
    • Years ago Joan Hebb created a handy Quickstart Guide. Follow the instructions for calibrating and clearing the mean values. 
    • Leave the fruit on the tree but ensure that leaves are not caught between the LED sensors and the fruit surface.
    • Take a reading on the average sides of each apple (imagine an apple has four sides, ignore the sun-exposed and shade-exposed sides and use the remaining two sides). 
    • Test a minimum of 20 apple samples randomly from each block by measuring 10 apples from one side of the row and 10 apples from the other side (10 apples x 2 fruit sides x 2 row sides = 40 readings). 
    • Record the average result calculated by the device then clear the mean value to start over in the next block. Keep your mean values because it will be helpful to compare blocks over time and between years. Record the block name and successive dates of measurement.
    • Honeycrisp with a DA meter reading above 0.59 is too immature to harvest, 0.59-0.36 is optimally mature and best for storage, and below 0.36 is over mature and susceptible to storage disorders so is best sold immediately (DeLong and others, 2014).
    • The DA meter boundaries for Ambrosia destined for long term storage are 0.47 to 0.28 (DeLong and others, 2016).

    Recommendations:

    • Take weekly observations on the same day to analyze the rate of change. Start taking sample readings 3-4 weeks before the predicted harvest date to anticipate the rate of change and the approaching start time. One of the major benefits of the DA meter is using the readings to chart the progression of maturity and to compare blocks so that more mature blocks can be harvested before others.
    • The DA meter values for optimum harvest may vary each year so it is still important to regularly do a taste test and starch test. The DA meter helps to increase the frequency of sample testing and the sample size.


    Reducing Bruising


    Recommendations:

    • Let fruit warm up before harvesting. Apples picked in the cool weather of early morning bruise more easily than those picked in the day’s warmth. Generally, susceptibility to bruising decreases gradually from 0 to 15°C.
    • Take the time to educate staff about the proper way to perform harvest activities that reduce bruising. For example, pick the bottom of the tree first, don’t overfill the picking bag, avoid long harnesses that let the bag bump against knees when walking, explain the difference between varieties etc.
    • Re-grade orchard roads prior to harvest to lessen bumps that would jostle fruit being transported in bins.
    • Have an inspector sample fruit from various positions in the bin two times each week and leave at room temperature for 24 hours to check for signs of bruise development.
    • If bins of fruit will sit in the orchard during overnight freezing temperatures, place the bins where they will be shaded from direct morning sun. Direct sun will warm the fruit too quickly and can lead to deep and lasting bruises.


    Considering Watercore

    Watercore is a fruit disorder closely associated with over-mature apples along with several other factors. It happens most frequently in years with high sunshine and lack of cloudy, rainy days. Also, highly coloured and large fruit are most prone to the disorder. Fruit with the disorder have an appearance of water-soaked flesh because the spaces between the cells become concentrated with sugars instead of air. Small signs of watercore can disappear in storage and add sweetness to fruit. However, more serious watercore can reduce gas exchange in the fruit and lead to internal breakdown.

    Recommendations:

    • Mature fruit are more likely to develop the disorder because as fruit mature the starches are converted to sugars. The sugar solution builds up in the fruit. Blocks that have a history of watercore should be harvested before other blocks.
    • Consider products to delay harvest maturity. Both ReTain and Harvista labels state delayed onset and incidence of watercore.

    Avoiding Internal Browning

    Internal browning is likely related to carbon dioxide injury. The disorder frequently occurs in overmature and large fruit that have high carbon dioxide concentrations. In particular, fruit harvested late in the harvest window are most susceptible because as fruit mature their ability to diffuse internal carbon dioxide concentrations decreases. The internal carbon dioxide builds up and increases the chance of injury. Consider using products that delay harvest maturity.




    Events and Notices


    NSFGA Summer Tour Digest - August 5, 2026

    The 2026 Nova Scotia Fruit Growers' Association (NSFGA) Summer Tour brought growers together from across Atlantic Canada and beyond for a full day of learning, discussion, and innovation in the Annapolis Valley. The tour highlighted how progressive orchardists are adapting to changing weather, evolving technologies, and new market demands while continuing to produce high-quality fruit.

    The day began at Noggins Corner Farm, where participants were challenged to consider some of the industry's most pressing questions: How can growers make every drop of water count? Which rootstocks are best suited to Nova Scotia conditions? How can soil health be improved for long-term productivity? And what technologies will help orchards become more efficient and resilient?

    At CAP Farms in Grafton, discussions focused on rootstocks and irrigation. Eric Chappel shared firsthand experiences with a range of rootstocks, highlighting the benefits and challenges of different systems and encouraging growers to compare their own experiences. Standout rootstocks for Honeycrisp included M.26 and G.214. 

    Attendees also explored three irrigation approaches, including overhead guns, permanent overhead systems, and drip irrigation with input from Ray MacKenzie (VandenBussche). As a fine mist from the overhead irrigation system drifted through the orchard, participants used a thermal camera to explore fruit surface temperatures and the potential for sunburn during hot weather. As rainfall patterns become less predictable, irrigation is increasingly being viewed as an important management tool for maintaining tree health and fruit quality.

    The second stop at WINK Apples in Billtown showed a new drip irrigation system and innovative soil health practices.  Harrison Van Meekeren discussed practical considerations with irrigation for those considering similar investments. Philippe Caron (Dubois) provided a behind-the-scenes look at irrigation infrastructure. Participants also learned about the farm's use of diverse cover crop mixtures, mulching strategies, and soil-building practices designed to improve organic matter, water retention, and orchard productivity.

    Following lunch, the tour moved to Stirling's Mountainside Farms, where Tim and Andy Stirling demonstrated how equipment innovation and technology can improve efficiency. Growers gathered for an impromptu demonstration of the front mount mower with back end sprayer. The farm also showed management techniques for producing premium Ambrosia apples, including tying down branches to improve fruit set and cropping consistency. Discussions at a new planting then shifted to moisture conservation, with participants examining the farm's long-standing use of hay mulch.

    The final stop at Wittenberg Farm focused on young orchard management. Evan Wittenberg highlighted their seven-wire fruiting wall system where they are also tying down limbs on Honeycrisp and Gala. Further thoughts on irrigation were shared by Tal Weil (Delta Irrigation). Throughout the day, conversations with researchers Erin Smith (AAFC) and Vicky Levesque (AAFC) reinforced the importance of healthy soils.

    Congratulations to the Nova Scotia Fruit Growers' Association for a successful tour! Many thanks to growers for openly sharing ideas, challenges, and lessons learned! While every farm is different, the innovation, collaboration, and a willingness to try new approaches continue to be defining strengths of Nova Scotia's apple industry.

    Check out the Nova Scotia Fruit Growers' Association on Facebook for more photos and their acknowledgements for generous sponsor support.




    Pest Management Guide

    We offer printable PDFs of the guides from our website:

    Online pest guides are also available without login (https://www.perennia.ca/pest-guides/) and with login on your Perennia account (https://www.farmdatatools.perennia.ca/).  Using the online tool you can filter for organic and conventional options, search for key information, and sort based on information of interest. 



    Edited by Michelle Cortens, Tree Fruit Specialist
    Perennia Food and Agriculture Corp.

    By Michelle Cortens at August 13, 2026
    Labels:

    Orchard Outlook Newsletter Vol. 26, No 14

    Thursday, July 30, 2026

    Summer Samples for Nutrient Analysis


    Leaf Tissue Sampling for Nutrient Analysis

    Nutrient levels in leaf tissues change throughout the growing season. The nutrient analysis for apple tree leaves has historically been done after terminal buds set and recommendations are based on that specific timing (late July and into August in Nova Scotia). Collecting samples prior to or after the specified period may give inaccurate nutrient level readings. Annual fertilizer applications should be based on tissue analysis reports and other factors such as pruning, vegetative growth and anticipated crop load.

    Recommendations:

    Collect leaves for nutrient analysis after terminal buds set on this season’s extension growth. Typically sampling is completed by mid-August.

    The protocol:
    • A sample usually represents a block of orchard 1 to 2 hectares in size.
    • Sample 10 apple leaves from each of 10 representative trees of the same variety for a total sample size of 100 leaves. Sample from the same trees every year to limit the variation between years. Try marking the tree with spray paint.
    • Collect leaves from the mid-point of the current year’s growth from throughout all sides of the tree.
    • Place the leaf samples in a paper bag.
    • If there are problem areas within the orchard, then sample trees in the problem areas separately.
    • The leaf sample needs to be submitted as soon as possible after collection in order to obtain an accurate nutrient analysis. If the sample cannot be submitted right away, refrigerate until it can be submitted.
    • Always label samples with the grower or farm name, mailing address, phone number, farm registration number, orchard block name, variety and sample number.
    • Take an accurate sample by reviewing some guidelines on Fruit Crop Tissue Sampling Guide and for help interpreting results review Understanding the Tissue Analysis Report. Further information is available on How to Take a Plant Tissue Sample.

    Soil Sampling for Nutrient Analysis

    A leaf nutrient test tells you whether a nutrient has been absorbed. A soil analysis, on the other hand, shows what levels are available to the root system. If a tree cannot uptake nutrients from adequate soil levels then perhaps your limiting factor is not related to nutrient availability and is more likely related to compaction, nematodes or pathogens affecting the root system. Or more simply, a soil nutrient test could determine a soil nutrient deficiency.

    Recommendations:

    • Soil samples do not need to be collected on an annual basis but should be collected at least once every three years.
    • Two to four soil cores should be taken at the drip line from each of 10 trees. The soil cores should be mixed and a representative sample placed in a soil box or sealable plastic bag for analysis. 
    • Early August is a good time to sample orchard soil unless the soil is unusually dry or recently leached by heavy rains. If the soil is too dry it is very difficult to extract full 0-15 cm (0-6") soil samples and a better sample will be obtained by waiting until light rain has moistened the topsoil.
    • Take an accurate sample by reviewing some guidelines on How to Take a Soil Sample and for help interpreting results review Soil Test Report Interpretation for Nova Scotia.


    Perennia Lab Services

    Effective May 1, 2026, Perennia is fully operating the former Nova Scotia Department of Agriculture (NSDA) Analytical Lab at the Harlow Institute Building, 176 College Road in Truro.

    In addition to mineral and bacteria water testing, we are conducting the same tests as previously offered: 
    • Soil analysis for lawn, garden and field samples
    • Soil amendment analysis
    • Greenhouse soil, nutrients and water + field, milk house water, etc.
    • Feed analysis
    • Digest samples
    • Plant tissue analysis
    We are also continuing to offer the 50 per cent discount on the same tests as when the lab was operated by NSDA for farmers with a current farm registration number. Our service fees also haven’t been changed and the overview PDF is available at https://www.perennia.ca/analytical-lab

    For drinking water samples, these tests can only be accepted at the Harlow Building in Truro.

    All other samples can continue to be dropped off at:
    • NSDA Digby and Antigonish offices
    • Nova Scotia Department for Natural Resources and Renewables Strathlorne Nursery in Inverness
    • Harlow Building in Truro
    • Perennia office in Kentville – Samples should now be dropped off at the Perennia Office instead of the NSDA office.


    Soil collection supplies can also be obtained at these locations along with submission forms and resources.

    All drop-off dates and times, locations, submission forms, how-to resource forms and interpretation guides, payment methods and fee listing are all available at www.perennia.ca/labservices where you can also order tests from our Plant Health Lab.

    For more information or questions please contact labs@perennia.ca

    By Michelle Cortens at July 30, 2026
    Labels:

    Orchard Outlook Newsletter Vol. 26, No 13

    Tuesday, July 7, 2026

    For the final weekly issue of the Orchard Outlook newsletter, we take a closer look at soil moisture management. While dry periods are a normal part of the growing season, last year reminded us that forecasted rain does not always arrive as expected. This article highlights practical strategies for conserving soil moisture, monitoring conditions with sensors and other tools, understanding irrigation triggers, and interpreting recommendations by soil type. We also discuss deficit irrigation as an option when water supplies are limited, balancing mild water stress to manage vegetative growth while avoiding excessive dryness that can affect tree performance. Current soil moisture readings suggest that sandy loam, loam, and silty loam sites have reached irrigation thresholds, although conditions will vary among orchards and should be confirmed with on-farm observations. Thank you so much to the members of the Orchard Outlook Committee!!

    *** Please note that this will be the last weekly issue of Orchard Outlook for the summer. Orchard Outlook will continue to be published occasionally for the remainder of the season as necessary. ***




    Table of Contents:


    Weather
    • 2026 Degree Day Accumulations
    • Soil Moisture
    • Apple and Pear - Codling Moth
    • Apple Maggot
    • Apple - Sucking Insects
    • Scale Crawlers
    • Obliquebanded Leafroller
    • Pear Insects
    • Follow Up on Pollination
    • Scion Rooting as Rescue Option for Weak Plantings
    • On-Farm Nursery
    • Tree Health
    • Nutrition
    • Suckers
    • Mowing
    • Pruning and Training
    • Cover Crops
    • Summer Hedging

    Events and Notices

    • Growing Good Growers - Thursday, July 9
    • Save the Date - NSFGA Summer Tour August 5

    Pest Management Guide



      

    Weather


    2026 Degree Day Accumulations


    The cumulative degree days are now on par with the 5-year average (Figure 1).  The 5-year average represents warm growing seasons on record so this year would also be considered among the warmest growing seasons.


    Figure 1: Heating degree day accumulations for plant (above 5°C) and insect (above 10°C) development from March 1 to July 7 for the past 17 seasons. Provided by Harrison Wright (AAFC Plant Physiology).
    • Approximately the same plant development heat units compared to the 5-year average, and 6% more compared to the 10-year average.
    • Approximately 4% less plant development heat units compared to 2025, and 2% less compared with 2024.
    • Approximately 1% more insect development heat units compared to the 5-year average, and 7% more compared to the 10-year average.


    Soil Moisture


    Dry periods are a normal part of the growing season, and typically they are less concerning when rainfall is expected to replenish soil moisture. However, last season reminded us that forecasted rain does not always arrive as anticipated. In recent weeks, forecasted precipitation has fallen short in the Valley.

    During last week's heat wave, there were reports of some leaf curling. Trees use leaf curling as a natural response to warm, dry conditions, reducing leaf surface area and helping conserve moisture. While this response does not necessarily indicate a problem, it brings soil moisture to the top of mind again.

    Conserve Moisture
    Regardless of how the remainder of the season unfolds, moisture conservation practices can help improve water-use efficiency and maintain more consistent soil conditions. Mowing, mulching, and regular soil moisture monitoring are worthwhile investments, particularly in blocks with lighter soils or a history of moisture stress.
    • Apply mulch early while the soil profile still contains moisture. Mulching is more effective when applied before soils become excessively dry. Apply a herbicide first.
    • Consider straw mulch, particularly on sandy knolls or lighter-textured soils. A layer only a few centimetres thick can reduce evaporation from the soil surface, moderate soil temperatures, and improve rainfall infiltration by protecting the soil surface.
    • Practice season-long mow-and-blow by directing laneway grass clippings into the tree row. Even a few centimetres of grass clippings can help conserve soil moisture while contributing organic matter to the soil.

    Monitoring Soil Moisture for Irrigation
    • Soil moisture can be monitored using the hand-feel method, tensiometers, or electrical resistance blocks. Sensors used in the Valley include: G Dot (electrical resistance blocks), and Spot On sensors (tensiometers). (These products are mentioned for general information only and not as endorsements.)
    • For more information on soil moisture monitoring methods, refer to Chapter 13 of the BC Trickle Irrigation Manual or OMAFA's publication Monitoring Soil Moisture. Irrigation scheduling can also be based on evapotranspiration estimates.

    Irrigation Triggers

    Drip Irrigation
    Drip irrigation is triggered earlier than overhead irrigation. Drip irrigation wets only a portion of the soil profile, so irrigation is initiated early to maintain the soil at a steady moisture level. Drip irrigation is triggered at 80% available soil moisture. 

    Overhead Irrigation
    Overhead irrigation wets a much larger volume of soil, providing roots with access to a larger water reservoir. As a result, overhead irrigation can typically be delayed until soils reach approximately 50% available soil moisture.

    Interpreting Centibar Readings
    Several Davis weather stations in the Valley are equipped with soil moisture sensors installed at a depth of 16 inches. These sensors use the electrical resistance method and report soil moisture in centibars (cb). On a scale from 0 to 200 cb: 0 cb represents very wet soil and 200 cb represents very dry soil. The interpretation of centibar readings depends heavily on soil texture because different soils hold water differently.

    General Irrigation Guidelines by Soil Type
    • Light soils like sandy loams should be irrigated at 15 to 40 cb. 
    • Loam soils should be irrigated at 40 to 80 cb. 
    • Heavier soils like silt loam should be irrigated at 50 to 100 cb. 
    • These ranges correspond roughly to the soil moisture range between 80% and 50% available soil moisture.

    Guidance When Water Supplies are Limited
    Where water supplies are limited, growers may consider deficit irrigation, which involves allowing soils to dry to the upper end of the recommended available water range before irrigating. 
    • Target thresholds include sandy loam: 40 cb, loam: 80 cb, and silt loam: 100 cb. This level of mild stress can reduce excessive shoot growth while continuing to support fruit development and overall tree health.
    • Avoid allowing soils to become excessively dry. As a general guideline sandy loam should not exceed 100 cb, loam should not exceed 120 cb, and silt loam should not exceed 140 cb.
    • Observations from last season also suggest that fruit from orchards irrigated heavily starting late in the season and until harvest time may have had reduced storage performance.

    Water Deeply
    Deficit irrigation involves extending the time between irrigation events, but each irrigation should still replenish moisture throughout the active root zone. Deep watering encourages deeper rooting and improves the tree's ability to access water reserves. This includes practices for overhead irrigation systems, in which run times should be sufficient to wet the tree root zone rather than only the surface soil or groundcover.

    Approximate water requirements for a deep irrigation to 2 ft depth are:
    • 1.4 inches of water for sandy loam
    • 1.7 inches of water in a loam soil
    • 2.3 inches of water in a silty loam
    Using your system's application rate, calculate the run time required to deliver the target water volume.

    General Davis Weather Station Sensor Observations
    Recent observations from Davis weather station sensors installed at a depth of 16 inches on sandy loam, loam, and silt loam soils suggest that irrigation should be considered in many orchards if it has not already begun.

    This recommendation is based on the following sensors: North Medford (NSW041) sandy loam, South Berwick (NSW034) sandy loam, Upper Falmouth (NSW007) loam, Avonport (NSW084) loam, and Lower Canard (NSW015) silt loam.

    The information shared here is meant to be used for general guidance. Soil moisture measurements within your own orchard remain the best guide for irrigation decisions. I am learning about irrigation alongside you, so please reach out if you have questions that I can try to answer. I hope this information is a helpful starting point to address pressing questions.




    Insects



    Apple and Pear: Codling Moth


    Recommendations:

    • If trap captures are below the treatment threshold but continue to build over time then treatment should be applied once a threshold is reached. When the time for apple maggot treatments arrives, the chemistries will also treat late codling moth.
    • The neonicotinoid insecticides (group 4 products) move into plant tissues over a period of about 24 hours. If it rains before the product is absorbed, the product on the surface is susceptible to wash off.
    • Approximately a week after application of Imidan, clean out the trap and start monitoring the trap. The capture of an additional 10 or more moths would indicate that a second treatment is required.


    Apple Maggot

    • The Apple Efficacy Guide may be used to compare the products that are registered for control or suppression of codling moth and/or apple maggot. Note that high label rates are often needed for activity on apple maggot.
    • In blocks that are being treated for codling moth, the control is extended to early maggot flies. 
    • The economic threshold is 1 maggot fly per orchard on a yellow sticky board (Figure 3). 
      • Apply a conventional treatment 7-10 days after the first fly is captured on a yellow sticky board or immediately after a female is captured on a red sphere.
      • In organic orchards, Surround can be used to deter egg laying and GF 120 fruit fly bait can be used for suppression of adult flies. Both Surround and GF 120 should begin to be applied immediately as flies become present in the orchard. The first maggot fly was caught at the Kentville Research Station this year on June 30.
      • Clean maggot traps 7 to 10 days after treating a block for maggot and monitor for new trap captures. Retreat if new maggot flies are caught.
    • Flies emerge over a period of time so for satisfactory maggot control, monitor the presence of apple maggot flies to inform treatment programs. Remember, a single female can lay hundreds of eggs so do not stop treatment prematurely.
    • Significant rainfall will wash off insecticide residues that are needed to ward off apple maggot flies. Re-treatment is required after 10-14 days or cumulative rainfall of 12.5-25 mm (0.5-1 inch). Danitol and products registered for suppression are expected to have a relatively shorter field residual life of 7-10 days. Insecticide residue should be maintained through to the end of August.
    • Chemical groups 5 and 28 target adult flies to prevents stings. Chemical groups 1 and 4 have activity on adults, eggs, and larvae meaning that they prevent stings and if an egg is laid the products also prevent survival of the larvae.
    • Sanitation through removing wild apple trees can help to prevent the buildup of populations that will migrate into orchards from the orchard perimeter.
    • Apple maggot flies are weak flyers so a border/perimeter spray of Imidan near known hotspots may be an approach to help kill adult flies from the source. (Being cognizant of the 22-day PHI and REI restrictions).
    • Apple maggots pupate in the soil and may not emerge until up to four years later. Therefore, several years of diligent management are required to reduce the resident insect population.

    Figure 2: An apple maggot fly on a 1 x 1 inch grid of a yellow sticky trap. The fly has a black F-shaped pattern on the wing that mimic's the shape of a spider's legs. It is slightly smaller than a common house fly and has a white dot in the middle of its back.


    Apple - Sucking Insects


    Aphids:
    • Green aphids have been building in population recently. Monitor if you are due for re-treatment. Green aphid will move back into orchards that were treated previously. 
    • Monitor for aphids in young trees and nursery plantings where feeding can disrupt shoot growth. If leaves are curling, high water volumes are needed for effectiveness. Assail also has activity on codling moth, apple maggot and leafhoppers. Be cognizant of REIs if installing trellis.

    Mites:
    • European red mite, two spotted spider mite and apple rust mite are the prominent species that affect apple trees. Although not directly damaging to the fruit, these mites in all their motile life stages can drain the nutrients from the trees and dramatically degrade fruit quality. 
      • Scout your orchards or check your scouting reports to see if there is a treatable population. Those growers with a consultant will receive the most accurate information because mite counts are done using a specialized machine for brushing and beneficial predators are noted as well. 
      • In a hot and dry year, mite populations can double in 7-10 days.
      • Good spray coverage is critical.
      • Mites have many generations per year and therefore have a high potential to develop resistance. For resistance management, it is critical to rotate miticide classes.
      • July is the time of year to control rust mite before foliage becomes bronzed in mid to late August.
      • All miticides are effective on European red mite and two-spotted spider mite but only products Nexter, Envidor, and Magister provide control of rust mite.
        • Envidor is slow acting so it requires early intervention. 
        • Acramite, Kanemite, Nealta, and Nexter provide quick knockdown.
    • Potato leafhopper: Feeds on the young leaves of terminal shoots leading to yellowing at leaf edges, and cupping that will eventually turn brown. Adults are pale yellow-green and walk sideways whereas the white apple leafhopper is white and moves forward and back. Monitor your scouting reports or updates.
      • Potato leafhoppers can transmit fire blight. Their presence in young plantings and nurseries is concerning, especially in areas of active fire blight infections. Insecticides labelled for leafhoppers are the group 4 products and they include Assail/Aceta, Cormoran, and Sivanto Prime.

    Scale Crawlers

    • If you had scale last year at the packout then they should still be monitored even if an oil application was used in spring.  
    • The scale that are under a waxy coating at this time of year are the adults that are about to give birth to live young. Those live young are the crawlers that leave the waxy coating and become susceptible to insecticides. Typically the crawlers are active in July at about 4-6 weeks post-bloom and with the heat this year they could be on the move early. 
    • Monitor for activity by using traps that are made by using black electrical tape (with adhesive side out) around the scaffold limbs of trees, in areas with known infestations. Crawlers yellow bodies will be caught on the tape when they become active.
    • When the crawlers are active, Movento with a surfactant is one of the most effective products. The neonicotinoid products Assail/Aceta and Closer may also affect crawlers.

    Obliquebanded Leafroller

    • Monitor or check scouting reports for larval populations. The caterpillar feeds on terminal shoot growth and also on apples, leaving a scar.

    Pear Insects

    • Pear Psylla: Refer to the management guide for product options.
    • Pear rust mite: Pear rust mite can go unnoticed until heavy russeting extending from the base to the top of the fruit. Growers that apply Agri-mek for pear psylla control would also obtain pear rust mite control. Nexter or Envidor would be other options for pear rust mite control.
    • Codling moth: Refer to the above information for apples.



    Horticulture



    Follow Up on Pollination

    It is possible to see which fruit were fertilized and which fruit were not, depending on the look of the seeds. The fertilized fruit have plump light green seeds. The fruits with failed fertilization have empty seed pockets with seeds that are shrivelled. Anecdotally, early flowering varieties (or regions that flowered early) appear to have fewer seeds, suggesting poor pollination conditions at that time.

    Figure 3: Left: Late flowering Honeycrisp fruitlets with full seed cavities (Photo by Joan Hebb). Right: Early flowering Gravenstein with empty seed cavities (Photo by Michelle Cortens).


    Scion Rooting as Rescue Option for Weak Plantings

    For whatever reason, sometimes a planting can be weak and fail to fill its space. Maybe trees have been exposed to environmental stressors or maybe the dwarfing rootstock was too small to begin with. Maybe frost heaving exposed more of the rootstock shank. In these situations, trees that scion root are generally the healthiest.

    Past local experience has shown that scion rooting can be a management option for weak plantings that fail to fill their space or struggle to thrive. Where scion rooting was used in the past on a weak block, the grower says they wouldn't hesitate to do it again. 

    For some there might be the concern of too much vigour from scion rooting. After covering the graft union, it took the trees about 5 years to set strong scion roots to become vigorous. Given the short lifespan of orchards there isn't much concern about trees in this situation getting too big. If to much vigour result, then management practices like summer pruning, apogee, and root pruning can keep the vigour in check.


    On-Farm Nursery

    • Scion leaders need support. Stakes should be placed on the side opposite from the bud so it pulls the bud toward the rootstock rather than away.
    • Monitor for green aphids.
    • Remember the importance of weed control in nurseries. Management practices now will impact the outcome of the final tree. Encourage the growing point to be successful!
    • Budding
      • As August approaches, find a source of bud wood that does not have a history of fire blight strikes. Trees that have shown signs of fire blight strikes or that are situated near fire blight infections should be eliminated as a source of bud wood. Cut bud wood fresh every morning if possible.
      • Occasionally sanitize all tools used for bud wood collection, storage, and budding by washing in detergent and water and disinfecting with sodium hypochlorite bleach. During bud wood collection and budding, frequently spray hand tools with fresh sodium hypochlorite bleach solution, diluted one part to nine of water.
        • If bleach is too tough on tools, Lysol and Pinesol at one part product to ten parts of water are good alternatives. Do NOT use rubbing alcohol because even at 70% to 99% concentration it allows bacteria to survive (California Agriculture 1991).
    • It is highly recommended that you water your nursery before and after budding to encourage callus formation and a healthy union. 
    • The vigorous Geneva rootstocks can fail to accept tbuds, and other propagation approaches like chip budding and bench grafting are recommended. In several situations now, tbudding G969 has resulted in failed bud unions. What appears to happen is that the Geneva rootstock overwhelms the tbud with excessive callus formation (Figure 5).

    Figure 4: Two different on-farm nursery situations where t-budding Honeycrisp on G969 failed in 2018 and 2025 due to excessive callus formation and an overly vigorous rootstock.

    Tree Health

    • Top dressing is not recommended after the end of June. Late release and uptake will prevent trees from hardening off before the winter. 
    • Around July the trees are storing reserves in the roots for next year’s growth. When they are storing reserves, late glyphosate applications can be damaging if taken up by root suckers and transported to the root system. Avoid the risk by avoiding glyphosate applications after the end of June.

    Nutrition


    Calcium:
    • The goal of foliar Ca sprays is to increase the concentration of Ca in the fruit and reduce the incidence of bitter bit. Begin calcium applications at 4 to 6 weeks after petal fall when fruit have reached the golfball stage at around 35 mm. Calcium applied at two-week intervals is better than occasional, high-rate applications. 
    • Ca has very low movement within the tree and needs to be applied directly to the fruit surface to be absorbed. Therefore, thorough coverage is important to cover developing fruit.
    • The recommended rate is 4.5 to 15.5 kg elemental calcium per ha (4 to 14 lbs of elemental calcium per acre) over an entire season spread over six to eight cover sprays. 
      • Low rates will not cause leaf burn but will likely lead to only minor control of bitter pit and likely will not enhance storage life of the fruit. 
      • High rates may lead to some leaf burn, give good control of bitter pit, and may also enhance storage life of the fruit.
      • Determine how much elemental calcium you would like to apply over a season and then work backwards to determine the required number of sprays. 
    • Calcium chloride flake (77% CaCl2) is the most economical Ca material to use but also the highest risk for foliar burn. Calcium chloride flake has a low risk of leaf burn when applied at the standard rate of 4.5 kg per 1000 L of water/ha (4 lbs/100 gal/ac).
      • Calcium chloride flake is 77% calcium chloride which is composed of one calcium and two chloride molecules. According to the weight of the molecules the calcium portion represents about 28% of the total weight. Therefore, our calcium chloride flake contains 28% elemental calcium.
      • For each spray at the standard rate of 4.5 kg per 1000 L/ha, the 28% portion that is elemental calcium is 1.3 kg/ha (1.1 lbs elemental calcium per acre).
      • The risk of leaf or fruit damage from calcium is highest in hot weather. Susceptible varieties can develop lenticel spotting if damaged. Target fast drying conditions for applications.
    • Risk of leaf injury may be enhanced by Captan. Incompatibility has been observed with Epsom salts, and liquid or emulsifiable pesticide formulations in some cases. Do not apply calcium with Apogee/Kudos. Note that nutrient product formulations with calcium may contain boron that would interact poorly with water soluble packaging.

    Suckers

    • Remove woody suckers by cutting or ripping to avoid resource competition, the risk of systemic herbicide uptake, harbouring pests like fire blight shoot blight.
    • If suckers are more prevalent because of exposed roots due to frost heaving, try to hill the soil to cover the roots.

    Mowing

    • As grass becomes long the extra surface area increases transpiration. Keep grass mowed to conserve moisture.
    • Keeping the orchard floor cover mowed pre-bloom will minimize flowers that attract bees, which increases the safety of post-bloom insecticide applications.
    • Mowing and herbicide strips help to prevent issues with two-spotted spider mite (John Michael Hardman).

    Pruning and Training

    • Select strong terminals on young trees and remove competing terminals to single the tops if there are no re-entry intervals active and before the shoots get woody.
    • Ensure that deer fencing is installed as soon as possible to protect new growth on young trees.
    • Newly planted trees should be pruned for tree structure and supported as early as possible after planting. Prioritize trees that are known to be brittle at the union, including many of the new Geneva rootstocks (G.11, G.41, G.16 etc).

    Cover Crops

    • Perennia has a series of videos about cover crops that can be accessed from our website.
    • Summer grasses such as pearl millet and sorghum-sudangrass that have been a popular choice can be planted from mid-June until early August.
    • For August and September plantings of cover crops, check out the factsheet about Fall Cover Crop Species Selection and Management that was written by Sonny Murray and Caitlin Congdon.

    Summer Hedging

    • A local study by Perennia in 2013 evaluated the regrowth on summer hedging using Ambrosia on M.9 and Gala. Results indicate that the last week of June = 6 to 21 cm of regrowth, first week of July = 4 to 12 cm of regrowth, and second week of July = 2 to 3 cm of regrowth. No regrowth is expected after terminal bud set around the first week of August although it was not included in the trial.
    • On vigorous trees, delay summer pruning until terminal buds have been set on vegetative shoots. Pruning prior to this on vigorous trees can promote bud break and weak shoot growth. 


    Events and Notices


    Growing Good Growers - Thursday, July 9

    Time: Thursday, July 9 at 11:00 am
    Topic: Interplants and the approach to replace drought stressed trees.

    Location: Birchleigh Farms. We will meet at the North side of Hwy 1 across from the Briar Patch. We will be in the Ambrosia on the east side of the block in the last two rows. Watch for the NSFGA and Perennia signs.

    Please bring your thoughts, experiences, and questions to join us for this discussion. There is no need to RVSP, and we encourage you to bring your own coffee and snacks. Everyone is welcome to attend!

    Save the Date - NSFGA Summer Tour August 5

    The 2026 NSFGA Summer Orchard tour will be held on Wednesday, August 5. Events like this are only possible through sponsorship. Contact NSFGA for sponsorship opportunities.



    Pest Management Guide

    We offer printable PDFs of the guides from our website:

    Online pest guides are also available without login (https://www.perennia.ca/pest-guides/) and with login on your Perennia account (https://www.farmdatatools.perennia.ca/).  Using the online tool you can filter for organic and conventional options, search for key information, and sort based on information of interest. 


    This Orchard Outlook has been published with the input of the Orchard Outlook Committee including this week's participants: Harrison Wright, Joan Hebb, Danny Davison, Ian Willick, Suzanne Blatt, and Colin Hirtle.

    Written by Michelle Cortens, Tree Fruit Specialist
    Perennia Food and Agriculture Corp.
    By Michelle Cortens at July 07, 2026
    Labels:

    Orchard Outlook Newsletter Vol. 26, No 12

    Tuesday, June 30, 2026

    How are you all doing? Summer is officially underway and this week’s Orchard Outlook continues with key reminders. After the dry weather in June, consider activities that benefit moisture retention. The start of July signals that the fruit cuticle is protected enough to consider Folpan/Follow as a fungicide. We also remind you that rubbing alcohol is not an adequate sanitizer against fire blight bacteria on tools. If you've used the new thinners Brevis or Accede, take a look at examples of minor leaf injury but note there is no concern for tree health based on the symptoms observed. On-farm nursery growers will find a few tips for upcoming activities. As always, thank you to the Orchard Outlook Committee for their continued dedication and contributions.




    Table of Contents:


    Weather
    • 2026 Degree Day Accumulations
    • 2026 Precipitation Update
    • Apple - Scab
    • Apple - Powdery Mildew
    • Fire Blight Infection Management
    • Apple - Black Rot
    • Apple - Brooks Spot
    • Apple - Flyspeck and Sooty Blotch
    • Apple and Pear - Codling Moth
    • Apple Maggot
    • Apple - Sucking Insects
    • Scale Crawlers
    • Obliquebanded Leafroller
    • Pear Insects
    • Symptoms of Minor Leaf Injury from New Thinners Brevis and Accede
    • Scion Rooting as Rescue Option for Weak Plantings
    • On-Farm Nursery
    • Tree Health
    • Nutrition
    • Suckers
    • Mowing
    • Pruning and Training
    • Cover Crops
    • Summer Hedging

    Events and Notices

    • Save the Date - NSFGA Summer Tour August 5

    Pest Management Guide



      

    Weather


    2026 Degree Day Accumulations

    The cumulative degree days are maintaining the same trend as the last few weeks by being ahead of the 10-year average and close to the 5-year average (Figure 1).  The 5-year average represents warm growing seasons on record so this year would also be considered a warm growing season.


    Figure 1: Heating degree day accumulations for plant (above 5°C) and insect (above 10°C) development from March 1 to June 29 for the past 17 seasons. Provided by Harrison Wright (AAFC Plant Physiology).
    • Approximately 3% less plant development heat units compared to the 5-year average, and 4% more compared to the 10-year average.
    • Approximately 5% less plant development heat units compared to 2025, and 6% less compared with 2024.
    • Approximately 5% less insect development heat units compared to the 5-year average, and 3% more compared to the 10-year average.


    2026 Precipitation Update

    Harrison Wright says, "We are continuing our sawtooth pattern of alternatively being either well above or well below the precipitation monthly averages. We received less than 50% of the June monthly average." (Figure 2). 

    Recommendations:

    • Applying mulch early in the season while the soil has moisture is more effective at retaining moisture than waiting until midsummer. Apply a herbicide first.
    • Explore using straw mulch, in particular in areas of sandy knolls or on lighter soils where trees struggled last year. Apply to a depth of only a few centimetres to simply provide a physical barrier that reduces evaporation from the soil surface. It also shields the soil from sun to lower the temperature and slows the impact from rain droplets to improve infiltration.
    • Alternatively, practice season-long mow-and-blow to move the laneway grass clippings into the tree row. Creating a few centimetres of grass clippings has a big benefit. 


    Figure 2: Monthly precipitation totals in 2026 (triangles) compared with the 25-year average (bar graphs). Provided by Harrison Wright (AAFC Plant Physiology).



    Diseases


    Apple – Scab

    Where primary lesions are present, secondary infections have been occurring and will continue during wetting events of sufficient duration. The minimum wetting required for secondary infections is 3 hours less than the wetting required for primary infections.


    Recommendations:

    • It has been 2 weeks since the ascospores were depleted, according to model predictions. Before you consider lengthening spray intervals, take a close look at the leaf canopy in the orchard to determine your risk of secondary infections. Lesions develop on the surface of a leaf and they are velvety brown in appearance. Check cluster leaves for early infections and the mature leaves on terminal shoot growth for mid season infections. 
    • Monitor for extended or heavy periods of rainfall because most fungicide residues are washed off by a cumulative total of 50 to 60 mm of rain (2 to 2.5 inches). Summer diseases are a risk if spray programs are stretched to this limit.
    • If adopting a lengthened spray interval, once the 10-day interval has been reached it is better to re-apply fungicide protection prior to rainfall/possible infection rather than after. 
    • Be aware of the re-entry periods on products for hand thinning. Captan has an REI of 15 days for high density plantings and 24 days for low-density plantings. Alternatively, the product Allegro is a quick re-entry product at only 24 hours but note the 28-day preharvest interval.
    • Folpan/Follow: 
      • Should NOT be applied between tight cluster and 30 days after petal fall to avoid fruit russeting. If petal fall was on the first week of June, then you may consider using Folpan/Follow in the first week of July for this timeline to be satisfied. 
      • Folpan/Follow becomes a good option in the summer weeks for scab control and protection from summer diseases. 
      • Note the REI of 12 hrs for general activities and 6 days for hand thinning. 
      • Folpan/Follow is considered a cousin to Captan and is similarly a hot product that has the potential to cause fruit russetting. Do not use Folpan close to oil sprays or products containing surfactants. Also, be wary of tank mixes with liquid nutrients that are formulated to maximize uptake.


    Apple – Powdery Mildew


    Powdery mildew infections can be expected when conditions are warm (10-25°C), humid and dry.

    Recommendations:

    • Trees are susceptible to powdery mildew infections for as long as new leaves are forming on growing shoots (until terminal bud set).
      • On large and mature bearing apple trees, the main economical concern is in protecting fruit against infection. Fruit infection causes stunting and russeting. However, fruit are only susceptible to infection during and shortly after bloom. The russet stretches as the fruit expands. In early June there were possible infection periods when fruit might have been susceptible. Fruit are no longer at risk of infection. 
      • Protection may continue on young plantings because severe infections can reduce shoot growth, which is most concerning for young, non-bearing orchards. Continuing protection this season will prevent infection of next year's buds (to protect next year's growth), and result in less carryover of inoculum to next year. Pay particular attention to susceptible and high-value varieties such as Honeycrisp and Gala. Product reapplication intervals can vary from 7-14 days.
    • There is industry resistance to group 11 products such as Flint so it should not be used for powdery mildew management. 
    • To avoid resistance development, do not use any products with powdery mildew activity more than two times consecutively (without rotating to another chemical group with powdery mildew activity).


    Fire Blight Infection Management

    Industry-wide email alerts have concluded. If you have a situation with blossoms still present please contact me directly for blossom blight updates on an as-needed basis.

    Recommendations:

    • Blossom blight infection symptoms are now visible.
    • Cut out infections when a period of 2 dry days are in the forecast. Leave prunings in orchard laneways to let dry thoroughly for several weeks. If cutting a whole tree consider letting it dry while attached to the trellis. Don’t make piles that will prevent the wood from drying. Do not work in trees when they are wet from dew.
    • As soon as you find fire blight infections, use an application of Apogee/Kudos (prohexadione calcium). Use a lower rate if trees have not filled their space or the full rate if tree growth is not an issue. The benefits of Apogee/Kudos:
      • Helps suppress the progression of infection to buy you time for cutting it out. 
      • Builds protection in nearby trees that may not yet be infected so that if infection were to occur, the spread would be already slowed. Where infections are numerous, apply prohexadione calcium to the entire block considering that ooze can infect at a distance of at least 0.8 km away.
      • Reportedly has the potential to reduce or prevent canker incidence on perennial wood.
    • To save time, it is not necessary to sterilize the tools often as long as all of your cuts are in fire blight areas and during dry weather. Several research studies have concluded a lack of benefit from sanitizing tools. Where there is a tradeoff because of limited labour, it is best to work quickly rather than to sanitize tools.
      • If you insist on using a sanitizer, the general recommendation is one part bleach to ten parts of water. If bleach is too tough on tools, Lysol and Pinesol at one part product to ten parts of water are good alternatives. Do NOT use rubbing alcohol because even at 70% to 99% concentration it allows bacteria to survive.
    • Monitor for shoot blight on suckers that can infect the rootstock.
    • Do not break off branches with fire blight infections as you navigate the orchard. Research shows that the bacteria becomes systemic in the tree because branches are not adequately removed. There are then a high number of new infections and significantly more canker tissue and cankers on structural wood. 
    • Prune out fire blight infections on young trees in the current year, don't wait for winter.
    • Remove fire blight strikes at least 2-4 ft below active infections to remove the leading edge of the bacteria. The younger the tree, the deeper the cut. Being aggressive at the first sign of symptoms will help prevent the re-occurrence of symptoms and the need for continuous cutting back. Repeat tree inspections.
    • If you feel confident that you can monitor the formation of a canker on a stub cut for later removal, then a stub cut may be appropriate. A 4-inch stub cut causes a canker to form on the stub before reaching structural wood like the leader of the tree. However, do not forget to remove the stub because otherwise the canker will serve as a source of bacteria. Mark the tree for revisiting.


    Apple – Black Rot


    Recommendations:

      • Based on our limited knowledge, the highest risk of infections is theoretically between petal fall and 4-6 weeks later.
        • A 10 hr wetting period at 16°C to 32°C allows infection. 
        • The optimum temperature for infection is 20°C to 24°C. 
        • There are few management options to cover such a long risk period. 
          • Captan has activity but note the REI for orchard activities. 
          • Merivon has activity but this group 7 + 11 product should not be used more than 4 times each year. Meanwhile, the short PHI and protectant activity are good to reserve for late season application for protecting apples being placed in long-term storage. 
          • Folpan has activity but should not be applied until 30 days after petal fall to avoid russet. 
        • We do not have a model for black rot infection but protection would need to be targeted prior to wetting and ideal weather conditions.
      • The fruit cuticle is sensitive to damage at this stage. Be cautious with spray mixtures (calcium, foliar nutrients) that could create an entry point for the pathogen.

      Apple - Brooks Spot

      Brooks spot is caused by a fungus that creates sunken, dark green lesions on the fruit. It is a minor disease that has been an issue on Honeycrisp in the past. The symptoms of Brooks Spot can resemble lenticel breakdown and bitter pit which are also common on Honeycrisp. Include a product for cover sprays that is labelled for brooks spot such as Inspire Super or Aprovia Top (or Folpan 30 days after petal fall).

      Apple - Flyspeck and Sooty Blotch

      These summer diseases develop on the surface of the fruit in midsummer until harvest. They are caused by fungi that overwinter in dead twigs and the fungi tend to cause more infections under conditions of moderate temperature, high humidity and rainfall. Usually this disease is associated with lack of fungicide residues from long fungicide reapplication intervals. Include a product for cover sprays that is labelled for flyspeck and sooty blotch such as Captan, Maestro, Inspire Super, Aprovia Top, Cevya, Allegro, Pristine, and Merivon (or Folpan 30 days after petal fall). Summer diseases such as flyspeck are a risk if spray programs are stretched beyond the limit.



      Insects



      Apple and Pear: Codling Moth


      Degree Day and Treatment Timing Predictions
      We are very grateful for the regional biofix dates set by Erika Bent, APM. The biofix dates for this season are June 13 for most regions and June 15 for late regions.

      Suzanne Blatt, AAFC, has run the degree day model today to predict when degree day thresholds will be met for treatments. The models were run on Tuesday, June 30 with a degree day threshold of 10 degrees (C) using Kentville weather station data.

      Codling Moth Treatment with Egg Hatch Products
      Products:       Assail, Delegate, Intrepid, Altacor, and Exirel
      Timing: The treatment timing for egg hatch products is 100 degree days Celsius from biofix.
      Prediction: The 100 degree day threshold was reached in early regions by June 27. Late regions reached the threshold on June 28.

      Codling Moth Treatment with Organophosphate
      Product:       Imidan
      Caution: All hand thinning activities must be completed prior to application. No hand thinning can occur on trees treated with Imidan.
      Timing: Control of codling moth with Imidan is typically slightly later at 140 degree days after biofix.
      Prediction: The 140 degree day threshold is expected in early regions by end of day July 1. Late regions by end of day July 2.

      Recommendations:

      • Monitor the forecast for rain and do not apply treatment before heavy rain. Codling moth lay eggs that hatch over a period of time. Late application may miss the first egg hatch and could result in a few codling moth entries but will still provide residual activity for future egg hatches.
      • If trap captures are below the treatment threshold but continue to build over time then treatment should be applied once a threshold is reached. When the time for apple maggot treatments arrives, the chemistries will also treat late codling moth.
      • The neonicotinoid insecticides (group 4 products) move into plant tissues over a period of about 24 hours. If it rains before the product is absorbed, the product on the surface is susceptible to wash off.
      • Imidan does not penetrate leaf tissue so it is a surface material that is susceptible to wash off under rainy conditions. 
      • Approximately a week after application of Imidan, clean out the trap and start monitoring the trap. The capture of an additional 10 or more moths would indicate that a second treatment is required.


      Apple Maggot

      • The Apple Efficacy Guide may be used to compare the products that are registered for control or suppression of codling moth and/or apple maggot. Note that high label rates are often needed for activity on apple maggot.
      • In blocks that are being treated for codling moth, the control is extended to early maggot flies. 
      • The economic threshold is 1 maggot fly per orchard on a yellow sticky board (Figure 3). 
        • Apply a conventional treatment 7-10 days after the first fly is captured on a yellow sticky board or immediately after a female is captured on a red sphere.
        • In organic orchards, Surround can be used to deter egg laying and GF 120 fruit fly bait can be used for suppression of adult flies. Both Surround and GF 120 should begin to be applied immediately as flies become present in the orchard. 
        • Clean maggot traps 7 to 10 days after treating a block for maggot and monitor for new trap captures. Retreat if new maggot flies are caught.
      • Flies emerge over a period of time so for satisfactory maggot control, monitor the presence of apple maggot flies to inform treatment programs. Remember, a single female can lay hundreds of eggs so do not stop treatment prematurely.
      • Significant rainfall will wash off insecticide residues that are needed to ward off apple maggot flies. Re-treatment is required after 10-14 days or cumulative rainfall of 12.5-25 mm (0.5-1 inch). Danitol and products registered for suppression are expected to have a relatively shorter field residual life of 7-10 days. Insecticide residue should be maintained through to the end of August.
      • Chemical groups 5 and 28 target adult flies to prevents stings. Chemical groups 1 and 4 have activity on adults, eggs, and larvae meaning that they prevent stings and if an egg is laid the products also prevent survival of the larvae.
      • Sanitation through removing wild apple trees can help to prevent the buildup of populations that will migrate into orchards from the orchard perimeter.
      • Apple maggot flies are weak flyers so a border/perimeter spray of Imidan near known hotspots may be an approach to help kill adult flies from the source. (Being cognizant of the 22-day PHI and REI restrictions).
      • Apple maggots pupate in the soil and may not emerge until up to four years later. Therefore, several years of diligent management are required to reduce the resident insect population.

      Figure 3: An apple maggot fly on a 1 x 1 inch grid of a yellow sticky trap. The fly has a black F-shaped pattern on the wing that mimic's the shape of a spider's legs. It is slightly smaller than a common house fly and has a white dot in the middle of its back.


      Apple - Sucking Insects


      Aphids:
      • Monitor for aphids in young trees and nursery plantings where feeding can disrupt shoot growth. If leaves are curling, high water volumes are needed for effectiveness. Green aphid will move back into orchards that were treated previously so continue to monitor. Assail also has activity on codling moth, apple maggot and leafhoppers. Be cognizant of REIs if installing trellis.

      Mites:
      • European red mite, two spotted spider mite and apple rust mite are the prominent species that affect apple trees. Although not directly damaging to the fruit, these mites in all their motile life stages can drain the nutrients from the trees and dramatically degrade fruit quality. 
        • Scout your orchards or check your scouting reports to see if there is a treatable population. Those growers with a consultant will receive the most accurate information because mite counts are done using a specialized machine for brushing and beneficial predators are noted as well. 
        • In a hot and dry year, mite populations can double in 7-10 days.
        • Good spray coverage is critical.
        • Mites have many generations per year and therefore have a high potential to develop resistance. For resistance management, it is critical to rotate miticide classes.
        • July is the time of year to control rust mite before foliage becomes bronzed in mid to late August.
        • All miticides are effective on European red mite and two-spotted spider mite but only products Nexter, Envidor, and Magister provide control of rust mite.
          • Envidor is slow acting so it requires early intervention. 
          • Acramite, Kanemite, Nealta, and Nexter provide quick knockdown.
      • Potato leafhopper: Feeds on the young leaves of terminal shoots leading to yellowing at leaf edges, and cupping that will eventually turn brown. Adults are pale yellow-green and walk sideways whereas the white apple leafhopper is white and moves forward and back. Monitor your scouting reports or updates.
        • Potato leafhoppers can transmit fire blight. Their presence in young plantings and nurseries is concerning, especially in areas of active fire blight infections. Insecticides labelled for leafhoppers are the group 4 products and they include Assail/Aceta, Cormoran, and Sivanto Prime.

      Scale Crawlers

      • If you had scale last year at the packout then they should still be monitored even if an oil application was used in spring.  
      • The scale that are under a waxy coating at this time of year are the adults that are about to give birth to live young. Those live young are the crawlers that leave the waxy coating and become susceptible to insecticides. Typically the crawlers are active in July at about 4-6 weeks post-bloom and with the heat this year they could be on the move early. 
      • Monitor for activity by using traps that are made by using black electrical tape (with adhesive side out) around the scaffold limbs of trees, in areas with known infestations. Crawlers yellow bodies will be caught on the tape when they become active.
      • When the crawlers are active, Movento with a surfactant is one of the most effective products. The neonicotinoid products Assail/Aceta and Closer may also affect crawlers.

      Obliquebanded Leafroller

      • Monitor or check scouting reports for larval populations. The caterpillar feeds on terminal shoot growth and also on apples, leaving a scar.

      Pear Insects

      • Pear Psylla: Refer to the management guide for product options.
      • Pear rust mite: Pear rust mite can go unnoticed until heavy russeting extending from the base to the top of the fruit. Growers that apply Agri-mek for pear psylla control would also obtain pear rust mite control. Nexter or Envidor would be other options for pear rust mite control.
      • Codling moth: Refer to the above information for apples.



      Horticulture



      Symptoms of Minor Leaf Injury from New Thinners Brevis and Accede

      • There is no concern for tree health based on the symptoms that are observed (Figure 4). 
      • The main point I want to make is to recognize the symptoms and realize what caused them so the symptoms are not mistakenly attributed to something else.
      • Brevis can cause leaf necrosis. The leaves damaged in this example are Honeycrisp at the 5-6 leaf position that would have been young leaves at the time of application.
      • Accede can cause minor leaf yellowing and drop. It is only obvious on the tree row below the tree.
      Figure 4: The new thinners Brevis and Accede cause minor leaf injury that is not a concern to tree health. 
      Be familiar with the signs so as not to attribute it to something else.


      Scion Rooting as Rescue Option for Weak Plantings

      For whatever reason, sometimes a planting can be weak and fail to fill its space. Maybe trees have been exposed to environmental stressors or maybe the dwarfing rootstock was too small to begin with. Maybe frost heaving exposed more of the rootstock shank. In these situations, trees that scion root are generally the healthiest.

      Past local experience has shown that scion rooting can be a management option for weak plantings that fail to fill their space or struggle to thrive. Where scion rooting was used in the past on a weak block, the grower says they wouldn't hesitate to do it again. 

      For some there might be the concern of too much vigour from scion rooting. After covering the graft union, it took the trees about 5 years to set strong scion roots to become vigorous. Given the short lifespan of orchards there isn't much concern about trees in this situation getting too big. If to much vigour result, then management practices like summer pruning, apogee, and root pruning can keep the vigour in check.


      On-Farm Nursery

      • Scion leaders need support. Stakes should be placed on the side opposite from the bud so it pulls the bud toward the rootstock rather than away.
      • Monitor for green aphids.
      • Remember the importance of weed control in nurseries. Management practices now will impact the outcome of the final tree. Encourage the growing point to be successful!
      • Budding
        • As August approaches, find a source of bud wood that does not have a history of fire blight strikes. Trees that have shown signs of fire blight strikes or that are situated near fire blight infections should be eliminated as a source of bud wood. Cut bud wood fresh every morning if possible.
        • Occasionally sanitize all tools used for bud wood collection, storage, and budding by washing in detergent and water and disinfecting with sodium hypochlorite bleach. During bud wood collection and budding, frequently spray hand tools with fresh sodium hypochlorite bleach solution, diluted one part to nine of water.
          • If bleach is too tough on tools, Lysol and Pinesol at one part product to ten parts of water are good alternatives. Do NOT use rubbing alcohol because even at 70% to 99% concentration it allows bacteria to survive (California Agriculture 1991).
      • It is highly recommended that you water your nursery before and after budding to encourage callus formation and a healthy union. 
      • The vigorous Geneva rootstocks can fail to accept tbuds, and other propagation approaches like chip budding and bench grafting are recommended. In several situations now, tbudding G969 has resulted in failed bud unions. What appears to happen is that the Geneva rootstock overwhelms the tbud with excessive callus formation (Figure 5).

      Figure 5: Two different on-farm nursery situations where t-budding Honeycrisp on G969 failed in 2018 and 2025 due to excessive callus formation and an overly vigorous rootstock.

      Tree Health

      • Top dressing is not recommended after the end of June. Late release and uptake will prevent trees from hardening off before the winter. 
      • Around July the trees are storing reserves in the roots for next year’s growth. When they are storing reserves, late glyphosate applications can be damaging if taken up by root suckers and transported to the root system. Avoid the risk by avoiding glyphosate applications after the end of June.

      Nutrition


      Calcium:
      • The goal of foliar Ca sprays is to increase the concentration of Ca in the fruit and reduce the incidence of bitter bit. Begin calcium applications at 4 to 6 weeks after petal fall when fruit have reached the golfball stage at around 35 mm. Calcium applied at two-week intervals is better than occasional, high-rate applications. 
      • Ca has very low movement within the tree and needs to be applied directly to the fruit surface to be absorbed. Therefore, thorough coverage is important to cover developing fruit.
      • The recommended rate is 4.5 to 15.5 kg elemental calcium per ha (4 to 14 lbs of elemental calcium per acre) over an entire season spread over six to eight cover sprays. 
        • Low rates will not cause leaf burn but will likely lead to only minor control of bitter pit and likely will not enhance storage life of the fruit. 
        • High rates may lead to some leaf burn, give good control of bitter pit, and may also enhance storage life of the fruit.
        • Determine how much elemental calcium you would like to apply over a season and then work backwards to determine the required number of sprays. 
      • Calcium chloride flake (77% CaCl2) is the most economical Ca material to use but also the highest risk for foliar burn. Calcium chloride flake has a low risk of leaf burn when applied at the standard rate of 4.5 kg per 1000 L of water/ha (4 lbs/100 gal/ac).
        • Calcium chloride flake is 77% calcium chloride which is composed of one calcium and two chloride molecules. According to the weight of the molecules the calcium portion represents about 28% of the total weight. Therefore, our calcium chloride flake contains 28% elemental calcium.
        • For each spray at the standard rate of 4.5 kg per 1000 L/ha, the 28% portion that is elemental calcium is 1.3 kg/ha (1.1 lbs elemental calcium per acre).
        • The risk of leaf or fruit damage from calcium is highest in hot weather. Susceptible varieties can develop lenticel spotting if damaged. Target fast drying conditions for applications.
      • Risk of leaf injury may be enhanced by Captan. Incompatibility has been observed with Epsom salts, and liquid or emulsifiable pesticide formulations in some cases. Do not apply calcium with Apogee/Kudos. Note that nutrient product formulations with calcium may contain boron that would interact poorly with water soluble packaging.

      Suckers

      • Remove woody suckers by cutting or ripping to avoid resource competition, the risk of systemic herbicide uptake, harbouring pests like fire blight shoot blight.
      • If suckers are more prevalent because of exposed roots due to frost heaving, try to hill the soil to cover the roots.

      Mowing

      • As grass becomes long the extra surface area increases transpiration. Keep grass mowed to conserve moisture.
      • Keeping the orchard floor cover mowed pre-bloom will minimize flowers that attract bees, which increases the safety of post-bloom insecticide applications.
      • Mowing and herbicide strips help to prevent issues with two-spotted spider mite (John Michael Hardman).

      Pruning and Training

      • Select strong terminals on young trees and remove competing terminals to single the tops if there are no re-entry intervals active and before the shoots get woody.
      • Ensure that deer fencing is installed as soon as possible to protect new growth on young trees.
      • Newly planted trees should be pruned for tree structure and supported as early as possible after planting. Prioritize trees that are known to be brittle at the union, including many of the new Geneva rootstocks (G.11, G.41, G.16 etc).

      Cover Crops

      • Perennia has a series of videos about cover crops that can be accessed from our website.
      • Summer grasses such as pearl millet and sorghum-sudangrass that have been a popular choice can be planted from mid-June until early August.
      • For August and September plantings of cover crops, check out the factsheet about Fall Cover Crop Species Selection and Management that was written by Sonny Murray and Caitlin Congdon.

      Summer Hedging

      • A local study by Perennia in 2013 evaluated the regrowth on summer hedging using Ambrosia on M.9 and Gala. Results indicate that the last week of June = 6 to 21 cm of regrowth, first week of July = 4 to 12 cm of regrowth, and second week of July = 2 to 3 cm of regrowth. No regrowth is expected after terminal bud set around the first week of August although it was not included in the trial.
      • On vigorous trees, delay summer pruning until terminal buds have been set on vegetative shoots. Pruning prior to this on vigorous trees can promote bud break and weak shoot growth. 


      Events and Notices


      Save the Date - NSFGA Summer Tour August 5

      The 2026 NSFGA Summer Orchard tour will be held on Wednesday, August 5. Events like this are only possible through sponsorship. Contact NSFGA for sponsorship opportunities.



      Pest Management Guide

      We offer printable PDFs of the guides from our website:

      Online pest guides are also available without login (https://www.perennia.ca/pest-guides/) and with login on your Perennia account (https://www.farmdatatools.perennia.ca/).  Using the online tool you can filter for organic and conventional options, search for key information, and sort based on information of interest. 


      This Orchard Outlook has been published with the input of the Orchard Outlook Committee including this week's participants: Harrison Wright, Joan Hebb, Danny Davison, Ian Willick, and Suzanne Blatt.

      Written by Michelle Cortens, Tree Fruit Specialist
      Perennia Food and Agriculture Corp.
      By Michelle Cortens at June 30, 2026
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