Читать книгу Manual of American Grape-Growing - U. P. Hedrick - Страница 24

Under the assumption, then, that climate, of all factors, is chief in playing providence to the grape, let us examine somewhat critically the relations of climate to grape-growing. When analyzed, the essentials of climate, as it governs grape-growing, are found to be six: first, length of season; second, seasonal sum of heat; third, amount of humidity in summer weather; fourth, dates of spring and autumn frosts; fifth, winter temperature; sixth, air currents.