This species has been cultivated as a food crop for many hundreds of years and, in that time, several quite distinct forms have arisen. The nomenclature of these forms is confused, to say the least, and by no means universally accepted. We have followed the treatment used by GRIN, though it is very likely to be revised in the future[].

Common Name: Chinese Savoy

General Information

Tat soi is an annual to biennial plant developed in cultivation from Brassica rapa. Growing from a non-fleshy taproot, it forms a rosette of spreading leaves and, eventually, a flowering stem up to 100cm tall.
Tat soi is often cultivated, especially in the Orient, for its edible leaves.

Known Hazards

The oil contained in the seed of some varieties of this species can be rich in erucic acid which is toxic. However, modern cultivars have been selected which are almost free of erucic acid.

Botanical References

Range

A cultivar of garden origin

Habitat

Not known in the wild.

Properties

Edibility Rating
Habit	Biennial
Height	0.20 m
Pollinators	Bees, Self
Self-fertile	Yes
Cultivation Status	Cultivated

Cultivation Details

Tatsoi has been developed in cultivation in the warm temperate zone of China. It can be grown as an annual from the temperate zone to the tropics and can also be grown in the cold season in the temperate zone, where it can tolerate temperatures down to around -10°c and can even be harvested from under the snow.
Succeeds in full sun in a well-drained fertile preferably alkaline soil[]. Prefers a pH of 5.5 - 7[]. Tolerates a pH in the range 4.3 to 7.5. Prefers a cool moist reasonably fertile soil[].
There are some named varieties.

Edible Uses

Leaves - raw or cooked.

Medicinal

None known

Other Uses

None known

Propagation

Seed - sow in situ in the spring and early summer.