There have been reports of some blueberry fruit injury following the freeze during the past weekend. I contacted Extension Plant Pathologist Dr. Phil Harmon to determine the best treatments for freeze damaged crops.
Dr. Harmon suggested that Botrytis blossom blight and fruit rot will be the main concern, considering the rapid warm-up and potential for rainfall in the next few days. He says that preventative applications of Pristine, Switch and Elevate are good options for Botrytis blossom blight and fruit rot management. It must be noted that BASF Fungicides, such as Pristine, may not be available since the company pulled blueberries from some product labels. As always with any pesticide, be sure to read and follow instructions on the product labeling.
As always, be sure to rotate fungicide modes of action to avoid building resistance. Information on modes of action and efficacy of recommended fungicides may be found in the Blueberry Integrated Pest Management Guide:
Dr. Harmon also has a publication dealing specifically with Botrytis at:
Please let me know if you have any questions.
Gary K. England
Multi-County Extension Agent III – Fruit Crops
Lake County Extension
1951 Woodlea Road
Tavares, FL 32778
(352) 343-4101 Ext. 2729
(352) 343-2767 Fax