Tree Fruit Newsletter — June 11, 2026
Thinning Outlook
Signs of thinning from our carbaryl plus NAA (PoMaxa, Refine) application applied 7 days ago were evident today, but not enough considering the heavy crop this year. Less than 30% of the fruitlets came off today. It looks like we could be applying more thinning later this week. I plan to give it one more day to check again before deciding on what thinners to apply and which blocks need it. Cortland, Evercrisp and Zestar! are fairly easy to thin so these would be the blocks that do not get another thinner. We will be trying Accede for the first time this year on other varieties, and perhaps another round of carbaryl with NAA on Golden Delicious. Many of the Golden Delicious fruitlets were still smaller than 15 mm. Ethephon is known to thin fruit when they pass the 15 mm diameter stage, but it comes with a greater risk of overthinning, particularly in warm weather.
Warm temperatures are forecast through the weekend which will favor good thinning.
Renae Moran
University of Maine Cooperative Extension: Tree Fruits
PO Box 179
Monmouth, ME 04259
(207) 933-2100
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