This cool-season crop grows best when daytime temperatures are in the 60°F. Grow in both spring and fall, but avoid mid-summer crops as hot weather can cause premature bolting. Like spinach, can be grown in the spring or fall. In fact, you may be able to get a continual harvest throughout both seasons if you time planting correctly. A member of the cabbage family, broccoli is rich in vitamins. Direct seeding of broccoli plants is possible. This is especially so with a fall crop. For the first summer harvest, start your broccoli seeds in early spring. For a fall harvest, start your seeds in midsummer. Broccoli transplants can grow in six to eight weeks for a summer crop and only five to six weeks for a fall crop. When growing transplants in the spring, you want to make sure to give them enough cold weather to harden off, but make sure they are protected from freezing temperatures.