Tree Fruit Newsletter — June 13, 2025
In this newsletter:
- Thinning Window Closing
- Stone Fruit Fungicides
- Summer Tour Announcement
Thinning Window Closing
Thinners applied early last week should be showing signs of efficacy by now. For applications that went on midweek, they make take a few more days. We applied thinner last Wednesday and have only seen a few fruits that are easy to pull off the cluster. Thinner activity has been slowed down by the cold temperatures that occurred earlier this week, so it may take a few more days to see the effects. Being able to easily pull off the fruitlet is the first sign. Do not try to bend it off the cluster, but instead, simply yank on the fruitlet. If it has been thinned, it will come off with ease.
Fruit diameter on the largest fruits are past 15 mm, so time is running out if you need to apply more thinner.
At Highmoor Farm and elsewhere in the southern half of Maine, the combination of poor return bloom and poor pollination has reduced the crop load. Some blocks of Honeycrisp that I have visited recently have very little return bloom which has been discouraging to see and will likely lead to excessive bloom next year. If this occurred in your orchard, and you have crop insurance, it is recommended that you report this to your agent soon. If you need a letter, I am able to visit the orchard for an assessment and to write a letter for your records.
Stone Fruit Fungicides
We have passed the ‘shuck off’ or jacket stage for stone fruit. This is when chlorothalanil becomes too harsh to use on stone fruits, and could burn the fruit surface. It’s also not labeled for use after this stage. Captan can still be used, but is harsh on plums when applied in summer. Avoid applying it to plums during hot weather.
Maine Pomological Society Summer Tour at Cooper Farms in Monmouth
July 9, 2025 from 9:30 a.m. to 2:30 p.m.
The Maine State Pomological Society and Cooper family cordially invite you to attend this year’s Summer Tour to be held at Cooper Farms at their Monmouth facility. To RSVP, call Renae Moran at (207) 713-7083 (or email at rmoran@maine.edu) by July 1. Preregistration is not required, but is certainly appreciated. Cost to attend the Summer Tour is $30. Admission for two grower-members or one associate member is included with annual dues. To pay dues, please contact Margie Hansel, the Society secretary (mhansel@maine.rr.com).
One credit pesticide applicator recertification pending BPC approval.
Tentative Agenda
9:30 a.m. — Welcome and Registration
10:00 a.m. — Tour of the packing house with Karen Killian and Cooper Farms staff.
10:45 a.m. — Hillary Peterson, Maine Department of Agriculture, Conservation and Forestry, the IPM Council of Maine.
11:15 a.m. — Advertising topic, to be determined
11:45 a.m. — Pomological Society reports from standing committees
Noon to 1:00 — Lunch
1:00 p.m. — Orchard Tour
The Monmouth orchard features Gala, Honeycrisp and its high-coloring strains, high density orchards, dwarfing rootstocks, and great views of the surrounding area.
- The Eco Apple program in action. Their website: For Growers – Red Tomato
- Glen Koehler, UMaine Extension, Apple IPM updates and what to look out for in late summer.
Directions to Cooper Farms — 155 Norris Hill Road, Monmouth, ME 04259
From the north and east:
I95 Exit 109b, go West on Rte. 202 (toward Winthrop) for 16 miles. Turn left on Norris Hill Road. Cooper Farms is on the left, a short distance past the Highmoor Farm orchards. Alternate routes exist.
From the south and west:
I95 exit 86, left on Rte. 9 and continue 0.7 miles, then take a right onto Pleasant Hill Road for 0.8 miles. Continue through the stoplight where the road becomes Rte. 132 (Wales Rd. and then Pond Rd.) for 4.6 miles. Take left onto Leeds Junction Road, travel 2.9 miles to Rte. 202. Take a right onto Rte. 202 and go 1.5 miles to the Norris Hill Road, and take a right. Cooper Farms is on the left, a short distance past the Highmoor Farm orchards.
Renae Moran
University of Maine Cooperative Extension: Tree Fruits
PO Box 179
Monmouth, ME 04259
(207) 933-2100
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