Tree Fruit Phenology Update
Tree fruit development across New Jersey progressed rapidly over the past week under continued warm conditions; however, a significant freeze event has resulted in widespread injury to blossoms and young fruit across much of the state. Reports from across the state indicate substantial losses in many orchards, particularly in low-lying areas and blocks that were at full bloom or petal fall during the freeze. The extent of damage varies by location, variety, and orchard conditions; growers are encouraged to assess injury at the block level before making management decisions.
In apples, early varieties such as ‘Pink Lady’ were at full bloom during the freeze event across the state and are likely to have sustained significant injury. Later varieties and northern regions may have experienced variable damage depending on bloom stage and site conditions. Surviving fruitlets, if present, will become more apparent over the coming week.
In pears, most varieties across the state were at or just past bloom during the freeze, and significant crop loss is being reported. More advanced Asian pears may have experienced higher levels of injury.
Peach and nectarine varieties in southern counties were largely at petal fall to early shuck split during the freeze, and many orchards are reporting severe crop loss. In northern counties, where bloom was still ongoing, damage levels appear variable but may still be substantial in exposed sites.
Despite crop loss, continued monitoring for pests and diseases remains important, particularly in blocks with surviving fruit or where tree health and next season’s production are priorities.
Management Considerations After Freeze
- Assess damage before making inputs.
Wait several days for symptoms to fully develop before making thinning, fertilization, or pest management decisions. Cut buds/fruitlets to check for browning of the ovary to determine viability. - Thinning programs may not be needed.
In blocks with significant crop loss, chemical thinning applications should be reduced or avoided. Where crops remain, adjust rates conservatively based on observed fruit set. - Maintain disease management programs.
Even in blocks with reduced crop, fungicide coverage should be maintained (e.g., apple scab, brown rot) to protect foliage and overall tree health. This is critical for supporting return bloom next season. - Fire blight risk remains important.
Damaged blossoms can still serve as infection sites. Continue to monitor models (e.g., NEWA) and apply bactericides where risk is high and viable bloom remains. - Insect management should be adjusted, not eliminated.
Continue monitoring key pests (e.g., Oriental fruit moth, codling moth, plum curculio). In blocks with little to no crop, insecticide programs may be reduced, but trunk and foliar pests that impact tree health should still be managed. - Focus on tree health and next year’s crop. Where crop loss is severe, prioritize maintaining healthy foliage through proper nutrition and disease control to support bud development for the 2027 season.
Apples
Apple Phenology Update
Apple phenology advanced rapidly across New Jersey over the past week under warm conditions; however, a significant freeze event has impacted orchards statewide. Most varieties were pink to full bloom during the freeze, with early varieties in southern counties, such as ‘Pink Lady,’ at full bloom and likely sustaining substantial injury. Later varieties and more northern regions may show variable levels of damage depending on bloom stage and site conditions.
As temperatures remain favorable, development will continue into petal fall, where viable fruit remains. This remains a critical period for disease management, particularly for fire blight, apple scab, powdery mildew, and cedar apple rust. Even in blocks with reduced crop, maintaining protection of foliage and any surviving fruit is important for overall tree health and return bloom next season. Monitoring for early-season insect pests should also continue, with management decisions adjusted based on crop presence and block-specific conditions.
Phenology Dates by County (earliest varieties)
| County | Green Tip | Tight Cluster | Pink Bud | Bloom | Petal Fall |
| Cumberland | 3/22 | 3/28 | 4/3 | 4/8 | 4/17 |
| Gloucester | 3/22 | 3/28 | 4/3 | 4/8 | 4/17 |
| Burlington | 3/22 | 3/28 | 4/2 | 4/13 | 4/22 |
| Mercer | 3/22 | 3/28 | 4/2 | 4/13 | 4/22 |
| Middlesex | 3/22 | 4/1 | 4/4 | 4/14 | 4/22 |
| Monmouth | 3/22 | 4/1 | 4/4 | 4/14 | 4/22 |
| Hunterdon | 3/22 | 4/1 | 4/10 | 4/17 | TBD |
| Morris | 3/26 | 4/4 | 4/11 | 4/17 | TBD |
| Warren | 3/30 | 4/4 | 4/13 | 4/17 | TBD |
| Sussex | 3/31 | 4/10 | 4/14 | 4/18 | TBD |
| Bergen | 3/22 | 4/1 | 4/4 | 4/14 | TBD |
Apple Scab
Models
Apple scab infection risk remains elevated as we move through bloom and into petal fall. Ascospore maturity continues to increase rapidly, and we are in a critical window for primary infection. While recent conditions have been relatively dry, upcoming forecasted wetting events may result in significant ascospore discharge and infection risk. Growers should continue to monitor forecasts closely and maintain fungicide coverage, particularly ahead of rain events. Models are available through NEWA and RIMpro.
Current Update using the Upper Deerfield Station
- ~69–74% ascospore maturity as of April 22–23
- ~43% cumulative ascospore discharge to date
- Forecasted to reach ~79–84% maturity by April 24–26
- Cumulative ascospore discharge forecasted to increase to ~78–82% by April 25–27
- A combined infection event is forecasted for April 25–26 with sufficient wetting and favorable temperatures for infection
Primary scab season is approaching peak discharge, and maintaining coverage through this period is essential to prevent the establishment of primary infections.
Management Considerations
Fungicide programs should be maintained through bloom and into petal fall, particularly ahead of the forecasted infection event later this week. Despite widespread freeze injury, protecting foliage and any remaining viable fruit is critical for both current and next season’s production.
Programs should prioritize control of apple scab, fire blight (where bloom remains), powdery mildew, and cedar apple rust, especially given increasing ascospore maturity and the upcoming wetting period.
Recommended Programs
- Protectant + single-site tank mix:
- Mancozeb or Captan + single-site fungicide (use reduced rate when tank mixing)
- FRAC 3 (DMI fungicides):
- Rally, Indar, Inspire Super, Topguard, Cevya
- Strong activity on scab, powdery mildew, and cedar apple rust
- FRAC 7 fungicides:
- Fontelis, Miravis, Sercadis
- Effective for scab and mildew, but limited rust activity
- Reserve Aprovia for summer bitter rot programs (max 4 applications)
- FRAC 7 + 11 or 7 + 9 premixes:
- Merivon, Luna Sensation, Luna Tranquility, Pristine
- Broad-spectrum activity; good fit during high scab pressure periods
- FRAC 9 or FRAC 1 fungicides:
- Vangard, Scala, Topsin
- Useful for scab, but do not control cedar apple rust
- Fire blight management:
- Rotate Kasugamycin, Streptomycin, and Oxytetracycline
- Kasumin is labeled only through bloom/petal fall
- Streptomycin and oxytetracycline can be used post-bloom (note: FireLine 45 allows only 1 post-bloom application)
- Consider Actigard, Apogee/Kudos, or other plant defense elicitors where appropriate
Key Reminders
- Time applications ahead of rain events – a significant infection period is forecasted around April 25–26
- Apply on a 3–7 day interval, tightening to 3–5 days during high-risk periods
- Do not relax fungicide programs despite crop loss – protecting foliage is critical for return bloom
- Powdery mildew remains active under dry conditions
- Do not tank mix Captan with oil due to phytotoxicity risk
- Rotate FRAC groups and preserve FRAC 11 fungicides for summer use
Monitor:
- NEWA models
- Weather/wetting events
- Phenology
Insect Update
Early control is critical to avoiding season-long pressure.
Ambrosia Beetle
- Significant flight activity has been observed across New Jersey, with high trap captures reported in multiple counties
- Activity remains elevated, particularly following recent warm temperatures
- Continue monitoring closely, especially in stressed, freeze-damaged, declining, or newly planted blocks, which remain highly susceptible
- Freeze-injured trees may be more attractive to ambrosia beetles, increasing risk even in blocks with little to no crop
Codling Moth (CM)
- Biofix has been set for southern New Jersey as of April 20, 2026
- No trap capture has occurred in northern New Jersey this season
- Begin tracking degree-day accumulations from this date to time management applications
- In blocks with viable crop, early-season control is important to prevent internal fruit feeding later in the season
- In blocks with little to no crop, CM management programs may be reduced, but monitoring should continue
Summary
- A significant freeze event has resulted in widespread blossom and fruit loss across many orchards
- Damage varies by block, and crop viability should be assessed before making management decisions
- Apple scab risk is approaching peak primary infection, with a major infection event forecasted around April 25–26—fungicide coverage is critical ahead of rain
- Fire blight risk remains in blocks with surviving bloom; continue monitoring models and applying bactericides as needed
- Even in low-crop blocks, maintaining disease control and tree health is essential to support return bloom for next season
Pears
Pear Phenology Update
Pear development progressed rapidly across New Jersey under recent warm temperatures; however, a significant freeze event has resulted in widespread injury to blossoms and young fruit.
Most European pear varieties in New Jersey were at full bloom to early petal fall during the freeze and are likely to have sustained substantial crop loss, especially in low-lying or frost-prone areas. Damage levels vary by block, and growers should assess viability over the coming days.
Asian pear varieties, which were generally slightly more advanced, may have experienced greater levels of injury in some locations due to increased sensitivity at later bloom stages. In northern counties, where bloom was still ongoing, damage appears more variable depending on site conditions.
Where viable fruit remains, development will continue into petal fall. Despite potential crop loss, maintaining disease management and overall tree health remains important to support return bloom and long-term productivity.
Pear Psylla
- Pear psylla activity remains generally low to moderate across southern New Jersey, though variability exists by block
- Freeze-damaged orchards may see increased psylla pressure, as stressed trees are more susceptible to colonization
Regional Observations:
- Gloucester County: None observed
- Salem County: Adults observed
- Burlington County: No activity observed to date
- Mercer County: No activity observed to date
As orchards move through petal fall and temperatures remain warm, psylla populations are expected to increase, particularly where eggs are already present.
Management Considerations
- Insecticide applications should target newly hatched nymphs, which are the most susceptible stage
- Timing is critical—applications shortly after egg hatch provide the most effective control
- Prioritize blocks with historically high pressure, current egg presence, or freeze stress
- Even in blocks with reduced crop, psylla management remains important to protect tree health and prevent honeydew/sooty mold buildup
Recommended Options
- Movento (IRAC 23) – excellent systemic control of psylla, scale, and aphids (apply with a spreading/penetrating adjuvant for best performance)
- Actara (IRAC 4A) – highly effective on psylla and aphids
- Assail (IRAC 4A) – good activity on psylla and multiple pests
- Belay (IRAC 4A) – effective option for psylla control
- Centaur (IRAC 16) – targets immature stages
- Sivanto Prime (IRAC 4D) – effective, softer option with good activity
- Agri-mek (IRAC 6) – strong option when applied with oil/adjuvant, especially for nymph control
Pear Diseases
Fire Blight and Early Season Management
As pear orchards move through petal fall, the primary bloom infection period is largely complete; however, fire blight risk remains a concern, particularly under warm conditions and in blocks with freeze-injured tissue.
The recent freeze may increase susceptibility, as damaged blossoms and succulent regrowth provide entry points for infection, especially during rain, wind, or rapid shoot growth.
At Petal Fall and Post-Bloom:
- Continue monitoring forecasts using NEWA for blight risk, especially following storms
- Discontinue streptomycin after petal fall (not labeled beyond this stage)
- Kasumin may be used up to petal fall only; do not apply afterward
- Focus on protecting actively growing shoots, particularly during warm, wet, or stormy conditions
- In high-risk situations, oxytetracycline (e.g., Mycoshield/FireLine) may be used post-bloom for shoot blight suppression
Management Considerations:
- Watch closely for trauma events (hail, wind, heavy rain), which can trigger infections
- Maintain heightened awareness in blocks with a history of fire blight or freeze injury
- Rapid shoot growth under warm conditions increases susceptibility—vigorous orchards are at higher risk
- Be prepared to transition to post-bloom shoot blight management strategies, including timely antibiotic applications where appropriate
Fungicide Considerations (Post-Bloom)
- Maintain protectant fungicides (e.g., Mancozeb, Ziram) for pear scab and Fabraea leaf spot
- Use FRAC 3, 7, and premix fungicides (e.g., Inspire Super, Merivon, Luna products) for broad-spectrum disease control
- Rotate FRAC groups to manage resistance and maintain program efficacy
- Continue coverage even in low-crop blocks to protect foliage and support return bloom
Pear Scab
RIMpro modeling indicates that infection risk is increasing rapidly, with a significant infection period developing April 25–27. Infection values are reaching moderate to high levels, indicating strong potential for primary infections during this window.
Ascospore availability remains high, and with forecasted wetting events and increasing susceptibility, this represents a critical period for disease management. Even as trees move beyond bloom, maintaining coverage is essential to prevent the establishment of primary scab infections.
At and Past Petal Fall
- Maintain protective fungicide coverage, especially ahead of the April 25–27 infection period
- Apply prior to rain events, as infection occurs during leaf wetness periods
- If ≥2 inches of rainfall occurs after an application, consider reapplication to maintain protection
- Conditions are favorable for infection under cool, wet weather with extended leaf wetness
Recommended Options
- Protectants: Mancozeb, Ziram, Ferbam
- Resistance-risk materials: Procure, Cevya, Flint, Merivon, Luna Sensation, Inspire Super
- Vangard – use in tank mix with a protectant
Summary
A significant freeze event has resulted in widespread blossom and fruit loss in many New Jersey pear orchards, with damage varying by block and site conditions.
- Most pear varieties in southern counties are now at petal fall to early post-bloom, while northern counties range from full bloom to late bloom
- Asian pear varieties, which were more advanced, may have experienced greater levels of freeze injury in some locations
- Pear psylla pressure remains low to moderate, but populations are expected to increase with warm temperatures and may be higher in freeze-stressed blocks
- Insecticide applications can resume at petal fall, with a focus on targeting early nymph hatch and prioritizing high-pressure or stressed orchards
- Pear scab risk is increasing, with a high-risk infection period forecasted around April 25–27—fungicide coverage should be maintained ahead of rainfall
- Fire blight risk remains elevated, particularly in blocks with freeze injury and actively growing shoots; monitor for trauma events and late infection risk
- Even in blocks with reduced crop, maintaining disease control and tree health is critical to support return bloom and productivity next season
- Continued scouting and close monitoring of weather conditions, pest activity, and tree response will be essential over the next 7–10 days
Peaches
Peach Phenology
- Peach and nectarine development progressed rapidly across New Jersey under recent warm temperatures; however, a significant freeze event has resulted in widespread injury to blossoms and young fruit, particularly in southern counties.
- Most varieties in southern New Jersey were at shuck split during the freeze, a highly sensitive stage, and are likely to have sustained substantial crop loss, especially in low-lying or frost-prone areas. In northern counties, where bloom was still ongoing, damage appears more variable depending on site conditions and variety.
- Development will continue to advance under favorable temperatures, with any surviving fruit progressing through shuck split into early fruit development. Over the coming week, growers should assess crop viability at the block level as injury becomes more apparent.
- Despite potential crop loss, maintaining disease management and overall tree health remains important to support return bloom and long-term productivity.
Brown Rot
Blossom blight risk is declining as orchards move through petal fall; however, brown rot remains a concern on young fruitlets, particularly under warm, wet conditions. The recent freeze may have increased susceptibility, as damaged blossoms and fruitlets can serve as infection sites.
Infection is favored during wetting periods between 41–86°F (optimal mid-70s), and risk remains elevated during extended wet periods. Fruitlets remain susceptible through shuck split, after which natural resistance begins to increase.
Management Considerations
- Maintain fungicide coverage through petal fall and into early cover, especially ahead of rainfall
- Focus on protecting young fruitlets, particularly in blocks with a history of brown rot
- If prolonged wetting occurred during bloom, ensure continued protection post-bloom
- Rotate fungicide chemistries to reduce resistance risk
Recommended Petal Fall / Early Cover Materials
- Effective options:
- Indar, Inspire Super, Luna Sensation, Merivon, Pristine, Cevya, Flint Extra
- Additional options:
- Rovral (prior to petal fall timing only)
- Captan (useful in cover sprays)
Notes:
- Many of the most effective materials (FRAC 7, 11, 3) also play key roles in pre-harvest brown rot control—plan rotations accordingly
- Avoid over-reliance on any single FRAC group
- Abound and Quadris Top are highly effective, but are phytotoxic to apples—do not use if the same sprayer is used across crops
Petal Fall / Early Cover Disease Programs
- Peach scab:
- Cankers begin to expand at bloom and by shuck split begin to shed spores during wetting periods, so protective applications should be initiated starting at petal fall.
- Captan or Captan/Topsin combinations are good for cover sprays after shuck split for blocks that had scab last year.
- Apply Flint Extra or Abound at petal fall for anti-sporulant activity in high-pressure blocks.
- Bacterial spot:
- Begin protection at petal fall in susceptible blocks using copper or Mycoshield, especially under warm, wet conditions.
- Avoid combining copper with captan especially if it has been overcast for several days.
- Rusty spot:
- Programs should begin at petal fall, with Rally commonly used as the first application.
Insect Update
Oriental Fruit Moth (OFM)
- OFM traps are active across New Jersey, with biofix set for April 7 in South NJ and April 15 for most counties in North NJ.
- Degree-day accumulation should be tracked from this date to properly time first-generation management. The first insecticides for first generation Oriental Fruit Moth control should be applied at 170-200 degree days (base 45 deg F) after biofix. This timing generally coincides with petal fall in peaches. Do not apply insecticides until all bloom is off regardless of degree day timing. No Insecticides for OFM should be needed where Mating Disruption is implemented.
- As blocks move through petal fall, growers should begin preparing for first cover applications targeting OFM larvae. Timings can be calculated using the degree day calculator at the NEWA website by choosing the weather station nearest your farm, entering the biofix date as the start date, and choosing base 45 in the “degree day type” menu.
- Keep in mind that plum curculio is also active at petal fall so an insecticide that targets both pests should be selected, like Asana or Avaunt.
| OFM 1st Generation Timing | |||
| Insecticide Type | |||
| County/Region | Degree Days
by 4/24 base 45 |
Conventional
170-200, 350-375 |
Diamide
100-150, 300-350 |
| Gloucester – Southern | 235 | 1st –4/18-4/23
2nd – |
1st –past
2nd – |
| Middlesex – Northern | 133 | 1st –4/30-5/2
2nd – |
1st – 4/22-4/28
2nd – |
Scale
- Delayed dormant oil applications are complete for most orchards.
- Where oil was not applied or in orchards where scale is a recurring problem, an application of Centaur at petal fall or Movento between petal fall and shuck split should “clean up” problem blocks. Centaur is recommended at 34.5 ozs./ac and Movento should be applied at 6-9 ozs./ac. A penetrant must be included to Movento as per the product label. Movento will also control green peach aphid when used at this time.
- Continue monitoring historically infested blocks and planning for crawler management later in the season if populations persist.
Green Peach Aphid
- GPA colonies begin forming sometime during bloom. Examine trees for the presence of colonies from pink to shuck split.
- Continue scouting as terminals expand, and colonies begin to establish.
- Count the number of colonies on ten trees and use a treatment threshold:
- Nectarines: 1 colony per tree
- Peaches: 2–3 colonies per tree
Lesser and Greater Peach Tree Borers
- Growers using mating disruption for borer control can begin placing dispensers around the end of April and should have them in place by mid-May.
Petal Fall Considerations
Insecticide applications can resume at petal fall.
- Target key pests including:
- OFM (timed by degree-days from biofix)
- Plum curculio
- Tarnished plant bug and other catfacing isnects
- Green peach aphid
Early applications should focus on preventing the establishment of first-generation pests, particularly in blocks with a history of pressure
Recommended Petal Fall Options
- OFM / Leafrollers:
- Altacor, Asana, Delegate, Besiege, Voliam Flexi
- Plum Curculio / Catfacing Insects:
- Imidan, Avaunt, Actara, pyrethroids (e.g., Warrior II, Lambda-Cy)
- Green Peach Aphid:
- Assail, Actara, Admire Pro
Summary
- Most peach and nectarine varieties in southern New Jersey are at petal fall to shuck split, while northern counties are at full bloom to petal fall.
- The freeze event earlier this week has resulted in significant impact across the state, although the effect on projected crop yield is currently unknown.
- Brown rot risk remains present, particularly during wetting events, with young fruitlets susceptible through shuck split.
- Maintain fungicide coverage through petal fall and into early cover, especially ahead of rainfall.
- OFM biofix was set for 4/7 for southern counties and 4/15 for northern counties, and growers should continue tracking degree-day accumulation to time first-generation management.
- Insecticide applications can resume at petal fall, targeting key pests including OFM, plum curculio, tarnished plant bug, and green peach aphid.










