Promalin as a rescue treatment for frost damaged apples

As I scan the temperatures around the state on Weather Underground this morning, it looks as I expected, that most orchards are likely fine (no damage) or okay (a little tolerable damage) after the freeze event we’re in. Some orchards however, especially inland and upland, and really especially inland and lowland (in lower areas where cold air settles), may have experienced substantial damage. Promalin plant growth regulator is labeled and has shown some efficacy when applied to trees at bloom to early fruit set for maintaining fruit development after a frost or freeze. Promalin is a gibberellin and cytokinin PGR mix that essentially fools the fruit into continuing to develop in the absence of a hormonal signal from seeds that were damaged or are not present if the ovary was damaged. Applications within 24 hours after the freeze are most effective.

If your orchard experienced temperatures below 28°F, consider contacting your agrichemical dealer asap this morning and applying Promalin. Label rate is 1-2 pints per acre in 75 to 150 gallons of water per acre.


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