Brassica rapa subsp. chinensis.
Also called bok choy, this Chinese leafy vegetable has been cultivated for more than 1,500 years across East Asia, and during the 20th century became established in kitchens worldwide thanks to its versatility, mildness and speed of growth. At full maturity, the head reaches 25 to 35 cm tall, formed of an upright crown of wide white (or green, depending on the line) petioles, fleshy like little spoons, topped with glossy dark green leaves fanning out. All the beauty of an architectural plant and all the utility of a substantial vegetable.
It's at this adult size that pak choi reveals its potential for longer, more structured preparations: whole head split lengthwise in two and pan-braised cut-side down with garlic, ginger and a drizzle of oyster sauce; quarters laid on the surface of a family hot pot or a miso noodle soup; petioles separated from leaves and stir-fried a little longer (the former take longer to tenderize than the latter); or simply steamed, just enough to keep their crunch. No waste — everything eats, from the tender leaves down to the firm base.
Grower's tip: Full-size pak choi demands a little more patience and space than the baby version, but remains a fast vegetable for those who want a serious harvest. In Québec, sow in two windows to avoid the summer heat that bolts it in a few days: early April to late May for the spring harvest, then mid-July to mid-August for the fall harvest (often the most beautiful, with dense, sweet heads improved by the first cool nights). Direct sowing preferred — it transplants poorly and the shock can trigger bolting. Space generously (20-30 cm) to let the petioles thicken properly. Harvest the whole head with a knife at ground level when well-formed.
- Open-pollinated. Biennial, treated as an annual. Insect-pollinated; crosses with other Brassica rapa (turnips, napa cabbage, other pak choi) — isolate for seed saving.
- Height: 25 to 35 cm at full maturity.
- Maturity: 45 to 60 days.
- Exposure: full sun in spring and fall; part shade mandatory in summer.
- Rich, fresh, well-drained, neutral soil. Space 20-30 cm apart in all directions.
- Direct-sow early April to late May, then mid-July to mid-August. Tolerates light fall frosts well, which even make the leaves sweeter.
