Cold weather vegetable. If purchased in the Spring, plant as soon as possible before it begins to flower and becomes bitter. If purchased in the fall, they are very frost tolerant and become sweeter with light frosts.
Keep plants well watered and harvest the outside leaves regularly to ensure a constant supply. Mature plants can be harvested by pulling up the entire plant before trimming off the stem with a knife. Once plants start to flower, put them in the compost bin as leaves will become bitter.