Like other members of the brassica family (broccoli, cabbage, kale and cauliflower), Chinese cabbages perform well in cool weather. However, temperatures below 50·F coupled with increasing day-length encourages bolting the formation of seed stalks. You can grow these Chinese greens in spring, but bolting is less likely if heads mature in the shorter days of fall. Also, heads that mature in cool weather don't have the strong flavor and poor texture that summer-maturing heads often have.
Chinese cabbages mature as early as 42-days from transplanting, so you can harvest mature heads in fall if you start seeds about 2 to 3-months before your first frost date. Long Island gardeners need to start seeds in July. Home gardeners, who usually don't need a lot of Chinese cabbage all at one time, can do succession plantings at 10 to 12-day intervals. I usually recommend 3-small plantings.
Some of my seed was started indoors in Late June through early August. My transplants are usually set out about 4-weeks later, as late as the first week of September. As far as direct-seeding, I feel it gives you uneven germination, so production is less uniformed. Also, you could have a dry spell in August that would delay germination of seeds sown directly in the soil.
Light frost can actually be a boon to Chinese cabbages. It increases the sugar content of the leaves, making them very flavorful.
As with lettuces and other staples of the fall vegetable garden, polyester row covers can help extend the harvest by sheltering plants from sever cold and wind. Row covers also provide excellent protection against flea beetles one of the most troublesome insects for cabbage growers
If you want to grow non-heading Chinese cabbages, don't be confused by the names Pak Choi, Pac Choi, Pak Choy and Bok Choy, all refer to the same basic type of loose-leaved Chinese cabbages.
Pak Choy is also the specific name for the most commonly grown type of non-heading Chinese. Pak Choy grows 8 to 14-inches tall with thick basal stalks narrowing to thin midribs. The stalks are capped with dark-green, spoon-shaped leaves on the plant that grows in an upright rosette form resembling Swiss Chard.
Green-stalked Shanghai Pak Choy, or Baby Pak Choy, has a mature height of just 6 to 8-inches. Harvested young, the entire plant may be steamed and eaten whole, as it is in southern China.
I approach insect control from the ground up. The best way to avoid
insect damage on pak choy is to ensure that the plants grow quickly and are healthy. Feed your plants when seedlings have 2-leaves. Balanced growing conditions contribute to the health of the plant, enabling it to grow quickly, yet preserving the quality.
I feed my direct-seeded plants with finely crushed basaltic rock and crushed oyster shells, Although another source of calcium, such as limestone, could substitute for the shells. Soil must be biologically active, so the minerals can be assimilated. I recommend topdressing the minerals with compost if your soil is poor.
Because pak choy generally are smaller than the heading Chinese cabbages you can get away with a closer spacing. Sometimes I direct-seed pak choy one-half to 1-inch apart, and later thins the 2-inch-tall plants to stand 2-inches apart. Eventually I thin the more mature plants to 4 to 6-inches apart. I use the thinnings in salad green mixes, then harvests the remaining plants at baby, mid-or-full size. Plants are edible even when they bolt. The blossom is delightful, similar to our broccoli.
Choosing which of these delicious and undermanding greens to grow this spring, or fall is probably the most difficult part of the job. With the many interesting, widely adapted varieties available, you too could find yourself putting Chinese cabbages and pak choy out front,
right where they belong.
1995 Growing Vegetables