Tatsoi, Brassica rapa is very similar to bok choy.  Tatsoi forms a flat rosette of succulent pale green stems and dark green rounded leaves. The great thing about this vegetable is that all parts are edible. Toss the young leaves in salads or soups.  Larger, more mature leaves can be stir fried. Yukina is a large form with a more upright growing habit and the leaves are heavily crinkled.  

Tatsoi is easy to grow from seed or seedlings and grows better and taste better during the spring or fall, but can be grown during the winter months with frost blanket protection during the coldest winter months and taste fabulous. 

Growing:  Amend soil well with compost and a high nitrogen fertilizer.  Make a slight impression into prepared soil with a bamboo stick or garden tool handle, approx 1/4" to 1/2" deep, sprinkle seed, pinch soil over seeds and lightly water.  Keep soil moist.  Seeds should emerge within 3-10 days.   If growing from a seedling, dig hole slightly deeper than pot and bring soil to root ball firming slightly.  

Harvesting:   Outer leaves can be harvested as the plant grows or harvest the entire plant around eight weeks.