Below is the carbohydrate thinning model outputs for Central Virginia. We used the weather station of Crown Orchard at Betesville, for temp. and solar radiation values. The model predicts carbohydrate deficit until May 14th, which is good for chemical thinning.

You may consider using the maximum rates of 6-BA (200 ppm), and NAA (10 ppm) and adding a non-ionic surfactant to your tank (see the table below) to enhance thinning efficiency.

We will start the model for Winchester/Frederick County when we reach a fruit size of 8 mm in Gala. As of today, the fruit size of our apple cultivars in the AREC’s research farm ranges between 4-5.8 mm (see the table below).