Brassica rapa var. chinensis. Yu Tsai Sum is a type of choi sum. This summer crop is also known as Yu Choi. Grown for tender flower bud stalks (yellow flowers) and glossy, bright green leaves, it is mild and sweet when cooked briefly. Stems will be 0.5-1cm (.25") thick if grown and watered well. This variety was tops in our trials for both taste and texture. For large plants, sow in rows 30-45cm (12-18") apart. Cut the flower bud stalk with a few leaves - new shoots will grow from a leaf axil. Plant Yu Tsai Sum seeds in early summer, up to 6 weeks before frost. Early spring plantings may bolt.
Matures in 40-60 days. (Open-pollinated seeds)