What Frosts Threaten Fruit Trees? 0 7

The roots of dwarf apple rootstocks and strawberries die at soil temperatures of minus 8-10 degrees, while the roots of wild forest apples and seedlings of 'Antonovka' suffer at minus 14 degrees. The root system is especially vulnerable during snowless winter periods.

During sharp frosts, the bark and wood at the branching points of trees and at the base of the trunks sustain significant damage, as physiological processes in these tissues conclude later than in other parts of the plant, making it difficult to prepare for winter dormancy.

Plants often suffer from frosts in late winter and early spring. During this period, sharp temperature fluctuations are observed: at night down to minus 10-15 degrees, and during the day up to plus 5-10 degrees. Daytime positive temperatures promote the onset of vegetation, causing tissues to exit dormancy, lose hardiness, and become less resistant to nighttime frosts. In such conditions, the bark of the trunks and flower buds, especially in stone fruit crops — plums, cherries, and sweet cherries — are susceptible to sunburn.

Late spring frosts can cause significant damage to the harvest, especially during the mass flowering of trees and shrubs. The most sensitive to low temperatures are stamens, pistils, and ovules. At temperatures of minus 1-1.5 degrees, the stigmas and ovules of plums and cherries die, and at minus 2 degrees — the young ovaries of apple trees.