Curds exposed to sunlight rapidly become discolored, rough in appearance and coarse in texture. Collard Greens - Break off older lower leaves when they are 8 to 12 inches long. New leaves grow for a continuous harvest. Leaf lettuce - Cut older, outer leaves when they are 4 to 6 inches long. Young leaves will continue to grow and can be harvested over a long period of time.
Larger leaves tend to become bitter and tough.
Parsley - Harvest throughout the season as leaves reach 3 to 5 inches in length. Radish - Because radishes mature quickly, at least two crops can be grown per season. Thin radishes early to 1 inch spacing between plants to ensure rapid, uniform growth and crisp roots. Radishes allowed to grow too long will become bitter. Tomatoes - Can be harvested when ripe or green.