Frosty Nights Create Havoc

HORT SHORTS

Scattered frosts continue to create havoc on plants in Ohio landscapes.  Randy Zondag and Erik Draper reported a heavy frost occurred this past Thursday in northeast Ohio and then temperatures dropped below freezing the next night also.  Jim Chatfield shared with the group his experience of driving by a field of blueberries, encased in ice in southern Ohio, where overhead irrigation had been used as frost protection for the blooms!  Certain areas of the state have been severely affected, while other areas have remained relatively unaffected. 

Frost damage can be very difficult to determine and predict its impact on the plant.  Confusion arises from the variability in damage caused to blooms, leaves and young, expanding twig tissue on the same plants side by side!  Frost may or may not damage the entire flower bud or it may just burn the tender petal tissues.  On the other hand, it may not damage the petal tissues at all but it may burn off just the pistils or stamens or just damage the ovary so that no fruit develops.  The flowers may not even be affected but the young, expanding twig, which is very succulent tissue, may freeze, causing the cells to rupture, leak and then turn brown.   This damage may occur on all, some or a just a few or none of the newly expanding tips.  It is this inconsistency and variability in plant damage from frost that creates either an exquisite diagnostic challenge or a full-fledged frustration!   The best answer for the question of "What will be the impact on the plant?" still remains… just wait and see.