Pak Choi (Brassica rapa subsp. chinensis) is a crisp, fast-growing cool-season vegetable suitable for USDA Zones 2–11 as an annual. Grow in full sun to partial shade, ideally with 4–6 hours of sunlight daily. Keep soil consistently moist and well-drained, and harvest when leaves and stalks reach the desired size. Plant in early spring or late summer through fall, avoiding periods of extreme heat. For cooking, rinse thoroughly and trim the base. Pak choi can be stir-fried, sautéed, steamed, roasted, or added to soups and noodle dishes; the tender leaves and crunchy stems can be cooked together or separately.