How important is soil temperature when planting a vegetable garden?
Different spring weather favors different vegetables. Cool-season vegetables thrive and produce bountiful crops during cool, early spring days when frost or snow is likely. They are intolerant of extremely hot weather. These vegetables germinate at a soil temperature of 40 degrees, but the optimum temperature is 65 – 75 degrees. “Hardy” vegetables, such as, broccoli, cabbage, kohlrabi, onions, lettuce, peas, radish, spinach, turnips will grow with daytime temperatures as low as 40 degrees. When it’s too hot their quality tends to decline and they toughen, lose sweetness or split. “Semi-hardy” vegetables such as, beets, carrots, cauliflower, parsley, parsnips, potatoes, and Swiss chard prefer 40 – 50 degree daytime temperatures without frost. Warm-season vegetable seeds germinate with a minimum of 50 degrees, but the optimum temperature is 80 – 90 degree. They require a long hot growing season. The hotter summer becomes the better they will do, provided they receive enough moisture. Usu
