The Complete Handbook of Yu Choy

Chapter 1: Understanding Yu Choy

Yu Choy is a fast-maturing, cool-season leafy green in the Brassica family, grown and eaten primarily in southern China and throughout Southeast Asia, though its commercial footprint now extends to any city with a significant East Asian or Southeast Asian population. Botanically, it is Brassica rapa subsp. chinensis var. rosularis, which places it in the same species as bok choy (var. chinensis) and the turnip (var. rapa), but it is distinct from those in a way that matters for every downstream decision you will make. If you are buying, selling, or cooking this green, the first thing to understand is that "Yu Choy" is not a single, uniform product but a name covering a range of growth stages and varietal selections that behave very differently in the heat of a wok and in the cold of a walk-in cooler.

The most common confusion is between Yu Choy and its close cousin, Choy Sum (Brassica rapa subsp. chinensis var. parachinensis). The distinction is simple once you see it. Choy Sum is harvested for its flower stalks and yellow flowers, and its stems are typically thicker, more hollow, and require a slightly longer cooking time. Yu Choy, in its standard form, is harvested just before or as the flower buds are forming but before the stems become fibrous. The plant presents as a rosette of broad, dark green, ovate leaves on separate stems that emerge from a central base. The stems are