Yu choy (also edible rape or green chouk uyn jak sum) is a green leafy vegetable used in Chinese and South-east Asian cooking. It is mainly 0.4"-diameter green branching stems, with some dark green leaves and yellow flower heads. Yu choy is related to bok choy (leaves used) and broccoli (flower buds used). Yu choy is harvested as the plant bolts, which is when the low-growing plant suddenly shoots up stems to support flowers.
Yu choy is related to:
- choy sum - 1"-wide stalks with some vertical spacing, less bitter, less likely to be damaged due to smaller size
- bok choy - 2"-wide stalks with very little vertical spacing, more bitter, more likely to be damaged due to larger size
- Chinese cabbage - tight head (Pekinensis group), very common