First Newsletter of 2026!
The Orchard Outlook newsletter will now be published every Tuesday on a regular weekly schedule during the main management season. In this first newsletter we review winter weather to find that in general the temperatures were reasonable. We discuss green tip predictions, and prepare for early season pests.
The Orchard Outlook Committee reconvened this morning and kicked off with thoughtful discussions. Please give a warm welcome to our volunteer contributors:
- AAFC - Jeff Franklin, Harrison Wright, Ian Willick, Suzanne Blatt, Shawkat Ali, Vicky Levesque, Jill MacDonald, and Heather Rand
- Industry Contributors - Larry Lutz, Keith Fuller, and Bob Prange
- Scotian Gold - Danny Davison, Joan Hebb, and Ariana Willick
- NSDA - Colin Hirtle
- NSCC - Mathew Vankoughnett
We congratulate Jeff Franklin on his recent award of Honorary Membership to the NSFGA for his active role in the Orchard Outlook committee and his support for the industry. I'm grateful to the dedicated members of this committee! Our weekly contributors will be listed at the end of each newsletter to recognize their contribution to industry.
Table of Contents:
- Winter Weather Review
- 2026 Degree Day Accumulations
- Moisture Discussion
- Green Tip Prediction
- Tree Reserves
- Bud Observations
- Apple - Scab
- Stone Fruit - Black Knot
- Stone Fruit - Peach Leaf Curl
- Delayed Dormant Oil - Cautions and Considerations
- Scale Insects
- Pear Psylla
- Efficacy of Herbicides
- Crop Safety of Common Herbicides
- General
- Pruning
- Fertilizing
- Liming
- Perennia IPM Season Kick Off
- Nutrient Management Planning Web Series
Weather
Winter Weather Review
The Environment Canada weather station in Kentville is used for comparison because long-term historical data is available. The average monthly temperatures in Kentville for this past season are shown in red in Figure 1. The average monthly temperatures in December and March were colder than the 5- and 10-year averages.
Figure 1: Average monthly temperatures from December through March for the past three winters, and for 5- and 10-year averages at Kentville AAFC.
Figure 2: Extreme minimum monthly temperatures from December through March for the past three winters, and for 5- and 10-year averages at Kentville AAFC.
2026 Degree Day Accumulations
Figure 3: Heating degree day accumulations for plant (above 5°C) and insect (above 10°C) development from March 1 to April 13 for the past 17 seasons. Provided by Jeff Franklin (AAFC Plant Physiology).
- Approximately 21% less plant development heat units compared to the 5-year average, and 4% less compared to the 10-year average.
- Approximately 23% less plant development heat units compared to 2025, and 14% less compared with 2024.
- Approximately 26% less insect development heat units compared to the 5-year average, and 6% less compared to the 10-year average.
Moisture Discussion
- Snowmelt that occurs in early March allows time for the soil surface to dry sooner making it easier to travel laneways.
- This past winter, early snowfall insulated the soil from freezing temperatures and prevented frost. Therefore, snowmelt was likely to percolate into the ground rather than run off the surface as erosion.
- Snowmelt was slow, which suggests a good opportunity for infiltration to help replenish moisture in the soil profile.
Bud Development
Green Tip Prediction
Over the last 16 years, the first green tip date of apple recorded in Orchard Outlook has ranged anywhere from April 6 (2010) to May 6 (2015). The average green tip date is April 20. Jeff Franklin helps us estimate green tip dates based on degree day accumulation from January 1.This year the prediction based on the weather forecast is for early varieties to reach bud break on Sunday, April 19 in Kentville. The estimate has an accuracy of about +/- 3 days and depends on the accuracy of the weather forecast. Compared with last year's bud break on April 20, bud break is currently expected to arrive at around the same time.
Tree Reserves
Local research provided a snapshot of stored nutrients and carbohydrates by performing a wood analysis of spur samples taken December 18, 2025. The research was funded by Perennia with additional samples funded by Scotian Gold and knowledge collaboration with Danny Davison at Scotian Gold and Harrison Wright at AAFC. The results were explained in depth at the NSFGA Spring Workshop on April 1 but a small summary is provided here:
- Apple trees are resilient. Last season’s drought created both resource limitations and savings.
- Trees shifted resource use, slowing growth and increasing soluble sugars to support survival. Carbohydrate reserves in spur samples were elevated and suggest that stored reserves are available to be remobilized in surviving trees.
- However, root reserves and health are unknown based on our research.
- Local research found nutrients mostly within normal ranges, suggesting trees balanced reduced nutrient uptake with lower demand. This is good news because nitrogen reserves did not appear limiting and are supportive of bloom.
- While reserves support early bud growth, fruit set will depend more on current-season photosynthesis. Stay tuned for discussion on fruit thinning as the season progresses.
- Overall, effects are complex but not entirely negative. This season, focus on recovery through modest pruning (not excessive removal of storage wood), and cautious nitrogen fertilization (don't push growth harder than stressed trees can sustain).
Bud Observations
On Saturday, April 11, in the Greenwich area the peach/nectarine buds were at swollen bud, pear was dormant but with some swelling, and European plum was dormant (Figure 4).
Figure 4: Bud development in an early region in Greenwich on April 11. Shown from left to right: peach/nectarine, pear, and European plum.
Diseases
Apple – Scab
Beginning at green tip, apple tissues are susceptible to infection from the fungus that causes apple scab, Venturia inaequalis. The environmental conditions for an infection are listed in the Modified Mills Table. Primary infections are caused by ascospores present in the leaf litter and infections develop on spur leaves, terminal shoots, and young fruitlets. Ascospore maturity is aligned with bud development so that mature spores are ready to be released when buds show green tissue. If not controlled, primary infections will create spores that generate secondary infections for the rest of the season. The best approach to fruit protection is to control primary scab.
Recommendations:
- If buds are not yet at the green tip stage, then they are not at risk of apple scab infection.
- Monitor for green tissue on early varieties that signal the need to apply a protectant fungicide prior to the first infection event. Protection will then need to be reapplied on a 7-day interval, with a shorter interval after wet weather (cumulative 1-2” rain) or rapid tissue growth.
- Good early-season fungicide options:
- Mancozeb products (manzate, penncozeb, dithane) are compatible with oil. They may be applied at up to 24 kg/ha/year whether that is up to 4 full-rate applications or up to 8 half-rate applications. The re-treatment interval is 7 days and the re-entry for pruning is 12 hours.
- Scala + half rate group M performs well in cool weather but needs tissue for uptake so likely best used as a second spray. Use before powdery mildew risk period because it has activity on scab only. The re-entry for pruning is 12 hours.
- Copper Spray + half rate mancozeb product should only be considered if there is less than 1/4 inch green tissue. Do not apply if frost is expected. Copper does not redistribute in rain so mancozeb is recommended to improve protection. Do not apply before heavy rain.
- Captan/Maestro and Folpan/Follow should be avoided within 7-14 days of an oil application. If you are not applying oil for European red mite, then these products can be used for early black rot management in high pressure situations. The re-entry for pruning after Folpan/Follow is 12 hours, and for Captan/Maestro is 4 days for low density and 6 days for high density.
- Allegro/Vantana/Downforce can be used within 1-3 days of oil. The re-entry for pruning is 24 hours.
- Buran is used post-infection only.
Stone Fruit – Black Knot
Growers have commented that there appear to be more black knot infections than usual. If more infections occurred, they should be traced back to the spring of 2024. The rough black gall is the fruiting body of the fungus and it takes 18-24 months to develop. If there is an increased incidence, it is not likely related to the drought from the previous season because infections were initiated sooner.
Recommendations:
- Prune limbs 15 cm beyond the knot and destroy knots (burn or flail mow).
- Remove knots before bloom. New shoots are susceptible to infection risk during active shoot elongation. Most infections are believed to occur just before or during bloom, or after petal fall.
- Removing the fruiting bodies will not eradicate the fungus in the orchard but it will help keep the pressure down.
- Flag wild trees surrounding the orchard that might also carry knots and remove them when time allows.
Stone Fruit – Peach Leaf Curl
- Applications are most effective when applied before bud swell. Delayed applications (still prior to green tip) will provide some but not complete control.
- Early infections (green tip to petal fall) are severe and are responsible for causing complete defoliation. Middle infections (6th to 12th leaf) cause symptoms of leaf margins and can cause partial deformation. Late infections (after 12th leaf) cause leaf margins to become moderately deformed in small sections. Fruit infections can occur during petal fall to 3-4 weeks later when there is a heavy rain event (>15 mm) and temperatures below 18°C. The onset of symptoms is about 10-30 days after infection.
- A protectant fungicide applied before bud break may provide adequate protection during a dry spring but it is possible to observe more infections in an unusually wet year if the protectant is washed off before the infection period is complete.
Insects
Delayed Dormant Oil - Cautions and Considerations
- When green tissue is present, do not use dormant oil 48 hours before or after freezing temperature. Oil that is applied before freezing temperatures breaks down and adheres to the plant tissues unevenly instead of the target insects. Also if the oil and water mixture freezes before it dries then the green tissue can be injured.
- For varieties with Delicious parentage (Ambrosia, Gala, Delicious), early applications of oil prior to tight cluster are less likely to result in bark blistering.
- Oil should NOT be applied to young trees.
- Consider the greater water volumes needed for large canopy trees that have not been pruned yet versus trees that have been pruned. Apply thorough coverage of the bark that is appropriate to the orchard situation.
Scale Insects
The best time to target scale is ideally just before the tree breaks dormancy or with a delayed dormant spray of oil by green tip. Scale cannot develop resistance to the smothering action of the dormant oil so the oil can help to slow resistance to insecticides. Also, the spring oil application is more effective than insecticides at reducing the overall scale population. After green tip, the scale insects start building their waxy coating so the oil does not affect them after they have built their defences.
- The timing for targeting scale is not similarly effective for mites. The timing for mites is geared toward egg hatch after bud break and closer to tight cluster. Target your oil application for the more important pest issue.
Pear Psylla
The first line of defence against pear psylla is the use of dormant oil to delay egg laying and synchronize control of pear psylla with later insecticide applications. Dormant oil application should be made before green tissue and as soon as possible.
Weed Management
There is generally a need for 3-4 herbicide treatments per season. To get out of the cycle of trying to manage large weeds with post-emergent herbicides, think about pre-emergent/residual herbicides as filling windows of time. Most residual products will give about 6 weeks of weed control. Use residual herbicides through periods of high weed germination like in spring. Post-emergent herbicides help with clean up when weeds are small. The risk of crop damage by using burndown products is minimized by practicing prevention and keeping weeds small.
The weed survey in orchards was updated by NSDA in the fall of 2025. The survey concludes the highest relative abundance of the following weeds: willow herb, dandelion, bedstraw, butter cup, clover, wood sorrel, vetch, groundsel, wild carrot, lamb's-quarters, chickweed, sow thistle, bent grass, and dock.
Efficacy of Herbicides:
Most residual herbicides need about 1/2" of rainfall within 7 to 14 days of application to deliver product to the germination zone and to activate the chemical by putting it in solution.
- Glyphosate and 2,4-D require daytime highs of 10°C-15°C after a night above 3°C to have good activity and weeds must be actively growing. Activity is best when applied from noon to 6 PM.
- Perennial weeds may be targeted in spring when new perennial plants are at the seedling stage. Other timings are spot sprays at the early flowering stage or during fall re-growth after a minor frost. Glyphosate and group 4 products are systemic and work on certain perennial plants.
- If weeds are already present, add a post-emerge to a residual herbicide to achieve control.
- Treat grasses early in their growth stage for best control.
Crop Safety of Common Herbicides:
- Note that residual herbicides can damage single tree replacements of young trees if the product is not registered for use on young trees. Keep this in mind if you are considering planting single tree replacements after the drought. Damage may occur by planting into soil with herbicide residue or by mistakenly applying new residual herbicide.
- Speaking of the drought, the following residual herbicides can persist longer than usual in extreme circumstances like drought:
- For Authority, instead of waiting the usual 2 years for reapplication, you should wait 3 years since your previous application. The label advises a 3-year replant interval under normal circumstances and extended an additional year to a 4-year replant interval after drought.
- For Chateau, the rotational interval is 1 year. However, the label also says, “After periods of extended drought longer rotational intervals may be needed.”
- For Alion, there is no specific mention of drought in terms of replanting, but waiting longer than 12 months might be advised.
- In the USA, there are concerns about Ignite causing bark cracking. The specific risks are yet to be defined but just be cautious that Ignite is not sprayed onto or drifts onto young tree bark.
- Chateau should not be applied after budbreak unless application equipment is shielded to prevent crop injury.
- If you are taking out orchard within the next 2-3 years for replanting, avoid applying residual herbicides. The Alion label says to allow at least 12 months from last application to replanting an orchard.
- When mixing residual herbicides, agitation is important to keep the product in solution. If the herbicide settles in the tank then it can be delivered in a high concentration and possibly result in crop injury.
Horticulture
General
- Keep ahead of brush because the spraying season will begin soon.
- Remove tree guards to prevent trunk diseases.
Pruning
- Plan ahead and watch re-entry intervals for pruning activities when fungicide programs begin.
- Ensure that youngest blocks are pruned first so growth is directed into desirable leader and terminal extension. Prioritize high value trees and then return to low value areas.
- Consider prioritizing pruning in fire blight blocks to finish prior to tight cluster when cankers begin oozing. Cut out cankers, whether fire blight or other diseases.
- Pruning may be delayed closer to bloom for vigorous Ambrosia to reduce its vigour.
- Mature blocks can be pruned later and are best when pruned prior to bloom.
- A handout for farm workers 'The Fundamentals of Pruning' is available in English and Spanish.
Fertilizing
- Bud break to bloom is the ideal time for granular fertilizer application to maximize tree growth.
Liming
- Lime soils prior to planting an orchard with rates according to your soil report. Early spring is an option but fall can be a more practical time to apply lime to a new site and lengthen the time for acidity to become neutralized.
- Orchard maintenance with surface applied lime twill take a number of years to adjust pH of the soil profile so it is best to apply annually or biannually where needed. If soil testing for pH, measure during the same time each year (August) as pH can change over the growing season.
- The provincial limestone trucking assistance program is open.
Events and Notices
Perennia IPM Season Kick Off
On April 21 from 12:00 PM to 1:00 PM join us on a webinar to kick off the 2026 growing season with IPM updates from your Perennia Specialists. First, we will go through the updates and features we’ve added to the Perennia Pest Guides this winter. Then we will review pesticide registration changes and how to prepare your sprayer for the coming season.You can receive one Pesticide Continuing Education Point for attending the session. Register on the Perennia website.
Nutrient Management Planning Web Series
Whether you're an agronomist, extension or industry professional, or interested in sustainable soil management, this series will give you valuable, actionable insights you can apply right away.
This series will be comprised of six webinars addressing the following topics:
April 13 - Soil sampling and basic soil properties relevant to nutrient management
April 20 - Importance of pH management
April 27 - Nitrogen management
May 4 - Phosphorus management
May 11 - Base cations
May 19 (Tues) - Manure and organic amendment management
Register online here to join!
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: Jeff Franklin, Larry Lutz, Joan Hebb, Danny Davison, Heather Rand, Harrison Wright, Mathew Vankoughnett, Colin Hirtle, Matt Peill, Dustin MacLean, and Jill MacDonald.
Edited by Michelle Cortens, Tree Fruit Specialist
Perennia Food and Agriculture Corp.
Perennia Food and Agriculture Corp.
