Chinese cabbage should be better known because it is not as strident in taste as its other cabbage relatives or broccoli. The Chinese have bred this particular vegetable for its mild flavour and is often found in Asian soups, stir-fries and stews. Being a Brassica, it is prone to the same issues that all Cruciferous and mustard vegetables need to deal with – caterpillar damage, slightly alkaline soil etc. One major difference between it and other cabbages like savoy for example, is that it forms firm cylindrical rather than round heads. You also need to recognize there are two types – some varieties resemble the bok choy/pak choy shape whilst the other is the tight heart which is considerably larger.
Like all cabbage, Chinese cabbage grows in relatively cool conditions – it is not one for the tropics or even for intense summer heat which is why it grows so well in temperate environments. The ideal growing temperatures are between 55 to 70 degrees F. and is usually picked in the autumn and early winter.
Prepare the seed bed with good soil and incorporate rich humus and compost to provide sufficient nutrient to develop the large heads. A high nitrogen fertilizer should also be applied to offer the most encouraging growth conditions. water retention is important as no cabbage enjoys arid growing conditions and the stress will cause bolting.
Prewater the seed bed.
Sow seeds about 1/4- to 1/2-inch deep in rows and 18 inches apart where they are to grow. The best sowing time is late February to April when the temperature is above 15 ºC or between 55 and 70ºF . Plenty of room is required and I grow them as I would Savoy cabbage. Sometimes, the seed germination is erratic so another seed, even three should be placed in the same space. If all come up, then simply remove the weaker seedlings and replant elsewhere or discard.
Once the seedlings have emerged, the plants can continue to be thinned with the strongest plant being left about 10 to 18 inches apart.
Maintain watering to give a uniform soaking all round but do not waterlog. Cover with cloches to prevent birds eating the young shoots. As with most cabbage, water in the morning to let the leaves dry although rain will of course prevent such rigorous watering treatment.
I often grow these cabbage with others. If you have michihli cabbage and pak choy which are also upright, leaves about 18 inches between them. If I grow savoy types or large spreading wong bok types, then give them 28-36 inches for the leaves to spread out.
Weed regularly using a hoe to reduce competition and minimise slug and snail damage. Throughout the summer, cover with mesh to prevent cabbage white butterflies laying eggs.