By Becky Wiepz and Dan Kielar
Station Updates
- Cherry harvest started throughout the county last week and will start on the Station on Monday. Fruit quality is looking very good even if size is a bit small in some of the blocks.
- Fireblight strikes were observed on station this week. At this time in the season your only management option is to prune out any observed strikes.
UW Madison/Extension Updates
- Managing Bitter Rot and Marssonina Leaf Blotch in Wisconsin Apple Orchards
- Wisconsin Fruit Crop Scouting Report: July 15, 2026
- Getting the Most Out of Summer Hedging in Your Apple Orchard
- 2026 Wisconsin Apple Growers Association Field Day Recap
Historic Growing Degree Day Comparison
| Date 7/18 | 2022 | 2023 | 2024 | 2025 | 2026 | 20-year avg. |
| Base 50 | 982.5 | 1083 | 1134.5 | 1051.5 | 1138.5 | 1071 |
Recent Weather at Peninsular Ag Research Station
| Date | Max Temp(℉) | Min Temp(℉) | Max Wind Gust(mph) | Daily Rain Total(in) |
|---|---|---|---|---|
| 7/11 | 82.8 | 55.8 | 11.6 | 0.0 |
| 7/12 | 87.3 | 63.1 | 19.9 | 0.06 |
| 7/13 | 95.2 | 70.0 | 16.1 | 0.0 |
| 7/14 | 95.0 | 75.9 | 17.2 | 0.0 |
| 7/15 | 87.1 | 64.2 | 12.3 | 0.0 |
| 7/16 | 80.2 | 60.6 | 10.1 | 0.0 |
| 7/17 | 84.0 | 62.2 | 12.8 | 0.54 |
| 7/18 | 80.8 | 59.4 | 22.1 | 0.0 |
If you’d like to see weather data for your area, visit https://wisconet.wisc.edu/
Apples
Growth Stage: Use low rate NAA 5-6 weeks after full bloom to enhance return bloom next year. Check your label for rate information
Seasonal Update: Foliar sampling for nutrient testing should be done between July 20th and August 7th or whenever terminal buds start to set.
| Pest | Presence | Notes |
|---|---|---|
| Borer species | Present | |
| Codling Moth | Heavy second generation flight is slowing down | 2nd generation sprays should go out with a follow-up spray 10-14 days later |
| Apple Maggot | Traps should be placed soon | |
| Leaf rollers | Flight continues | Red banded leaf rollers coming to an end and oblique banded leaf rollers at peak flight |
| Disease | Presence | Notes |
|---|---|---|
| Apple Scab | Lesions detected in Northern Door County | Primary spore dispersal is nearly done (99% in Sturgeon Bay). If control was good, sprays can be stretched to 10-14 days between applications |
| Fire Blight | Strikes detected in Southern and Central Door County | Orchards should be monitored and strikes should be removed promptly, cutting 12-18 inches past the end of the canker. |
| Powdery Mildew | Strikes detected throughout the county | If present, include a product that specifies control on the label and plan on and early season application of sulfur next year. |
| Sooty Blotch/Flyspeck/Summer Rots | Apply preventative sprays before rain events, using NEWA models to determine spray timing. |
Cherries
Growth Stage: Fruit is starting to color.
Seasonal Update: New leaves are still expanding so good fungicide coverage is essential for season long tree health. Gibberellic acid application can be used to manage return bloom when applied 14-28 days after full bloom. See the article linked below for more information.
| Pest | Presence | Notes |
|---|---|---|
| Spotted Wing Drosophila | Heavy flight throughout county | Fruit is vulnerable throughout the county and insecticides should be used to protect fruit through harvest. When possible, save short PHI chemistries for applications closer to harvest. |
| Cherry Fruit Fly | Adults Detected | Make sure the CFF is on the label for your SWD sprays. |
| Borer species | Adults Caught | Targeted sprays should go out 7-10 days after first catch followed by a second application 10-14 days later. |
| European Red Mites | A few adults present in Southern Door | Scouting starts soon to monitor population build up. |
| Disease | Presence | Notes |
|---|---|---|
| Cherry Leaf Spot | Yes | Lighter pressure due to less rain events, but keep track of sprays during harvest to prevent flareups. |
| Powdery Mildew | Present in many blocks throughout county | High temperatures and humidity are increasing the pressure and spread of PM. Check your blocks if you are unsure. If present, include a product that specifies control on the label and plan on and early season application of sulfur next year. |
GRAPES
Growth Stage: E-L Growth Stage 29
Seasonal Update: Fungicides should be applied before bunch closure to protect your fruit through harvest.
| Pest | Presence | Notes |
|---|---|---|
| Leaf Hoppers | Yes | |
| Phylloxera | Some galls observed | |
| Red Banded Leaf Rollers | Yes |
| Disease | Presence | Notes |
|---|---|---|
| Black Rot | Single Lesions Observed | Early season fungal control is critical to prevent diseases from reaching economically damaging levels. |
| Powdery Mildew | None Detected | Risk will increase with current heat and humidity. Scout your orchard to determine local pressure. |
| Downey Mildew | None Detected | Risk will increase with current heat and humidity. Scout your orchard to determine local pressure. |