Many winter vegetables started in October or November are ready for harvest now. To enjoy their sweet tender leaves, cut cabbages when they are rock-hard; if they feel springy, they need more time. When broccoli buds are full and firm, cut the stalk with a knife. Leave both cabbage and broccoli in the ground and they'll continue to produce, especially with the benefit of a side-dressing of vegetable fertilizer. Cauliflower, though, forms only one head. To keep it snowy white, pull the leaves up over the head and tie them to block out the sun. Harvest when the buds are full and close together. When they begin to separate, you’ve waited too long. If you haven’t grown lettuce, now is still a good time to plant seeds or transplants. The cool weather will give you a crop quickly, and “the cut and come again†harvest keeps you in fresh salad greens for weeks.