kai lan

Sow seed outdoors in deep, fertile but firm, soil that isn't too acidic. If space is limited, start the seeds in modules or seedtrays and plant outside when big enough to handle easily (about 5 or 6 leaves). Watering through the summer months is very important. For more advice see vegetable cultivation

No pruning necessary

May be susceptible to flea beetle which can prevent seedlings from thriving and attacked by caterpillars when eggs laid by butterflies, hatch and feed. It is very popular food for pigeons which only netting can prevent. It is also eaten by snails, although once plants are established, this damage isn't usually severe. The cabbage root fly can cause failure to thrive and a heavy infestation of mealy cabbage aphid can spoil the harvest

May be susceptible to brassica downy mildew and brassica white blister. In areas where brassicas have been grown before, clubroot can build up in the soil