There has been some talk about the use of promalin to help overcome the damaging effects of freezing temperatures. Only a small amount of research has been conducted on this. Dr Steve McArtney showed that promalin applied after damaging freeze events could increase parthenocarpic (seedless) fruit development. Keep in mind this was only shown to be effective for freezes during full bloom. Also the rescue treatments were applied within 5 hours of the frost events. It is unknown whether promalin will have similar effects if applied at times other than bloom. Also, we don’t know how soon after the freeze event promalin needs to be applied to increase fruit set. In Dr. McArtney’s research, promalin did increase fruit set, but only to about 25% of a full crop.
