July 6, 2026

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By Becky Wiepz and Dan Kielar

Station Updates

• A new block of Honeyberries was planted for the UW Madison Emerging Crops program. These are part of a variety trial replicated at a number of sites that should have harvest data available in a few years.
• Cherry’s are moving from straw to blush and we expect harvest will start here in 2-3 weeks.

UW Madison/Extension Updates

• Honeyberry Field Day – Spooner Ag Research Station July 9, 2026
• Wisconsin Fruit Crop Scouting Report: July 1, 2026
• Notes from the Field: A Grower’s Perspective – Erin Warner #5
• Adjusting Nutrient Management After Frost: Apple Blocks Carrying a Light Crop
• Wisconsin Orchard Update: Secondary Apple Scab and Marssonina Leaf Blotch

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Historic Growing Degree Day Comparison

Date 7/5	2022	2023	2024	2025	2026	20-year avg.
Base 50	766.5	873.5	876	821.5	843.5	825

Recent Weather at Peninsular Ag Research Station

Date	Max Temp(℉)	Min Temp(℉)	Max Wind Gust(mph)	Daily Rain Total(in)
6/28	72.7	55.8	16.8	0.0
6/29	77.7	66.4	19.9	0.06
6/30	89.2	69.3	21.0	0.0
7/1	85.6	67.6	30.6	0.42
7/2	81.0	68.2	19.9	0.41
7/3	90.2	68.5	12.8	0.0
7/4	79.2	65.3	11.6	0.0
7/5	80.2	63.3	12.8	0.0

Apples

Growth Stage: 20+mm fruit in most varieties
Seasonal Update: Use low rate NAA 5-6 weeks after full bloom to enhance return bloom next year. Check your label for rate information.

Pest	Presence	Notes
Borer species	Present
Codling Moth	Heavy second generation flight has started	1st generation sprays should go out with a follow-up spray 10-14 days later
Plum Curculio	Scarring detected throughout county	Controls should go be included in your second cover spray
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.

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.
Plum Curculio	Adults Detected	Few egg laying scars have been detected, 1 more spray should be adequate to keep larvae out of the fruit at harvest.
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	Heavy pressure throughout county due to steady rain and warm temperatures. Application windows should remain tight as long as leaves are expanding and rain events continue.
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 27
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.

Additional Resources

• Gibberellic Acid Applications in Cherries
• Financial Decisions for Tart Cherry Crops with Variable Yields
• Take Steps To Ensure That You’re Complying With the EPA Herbicide Strategy To Protect Threatened and Endangered Species