Frost-Free Period

a part of the year when the temperature stays continuously above 0° C in an average calculation over several years. This period lasts from the long-term average date of the last spring frost to the long-term average date of the first autumn frost. In the northern regions of the USSR the frost-free period is less than 150 days. (On the Iamal and Taimyr peninsulas it is about 45 days.) In the west and south of the country it is 250 days and longer. (In the region of Batumi and on the southern coast of the Crimea it lasts 300 days and longer.) In the temperate zones it corresponds approximately to the growing season, whose duration significantly determines the composition of the local wild and cultivated vegetation.