Lettuce

Growth pattern: Lettuce is a cool-weather crop that can be cultivated in one of two ways. It may be grown as head lettuce, where a single seed is allowed to mature to form a single head of lettuce (what you would traditionally see in the produce aisle). Alternatively, lettuce may be cultivated as baby greens, where many seeds are sown closely together and harvested when the leaves are still young (what you see packaged as lettuce mixes or mesclun in bags or clear clamshell containers in the refrigerated section of your produce aisle).