Culture
Easily grown as an annual in fertile, organically rich, consistently moist but well-drained soils in full sun. Tolerates light shade. For culinary purposes, certain plants in this genus may be grown in home gardens by seed as annuals for harvest of mustard greens. Sow seeds directly in the ground in early spring 3/4” to 1” apart with 2’ between rows. Thin to 4-6” apart. Floating row covers are useful. Best to water plants early in the day so that they will dry off before nightfall, thus reducing the likelihood of attracting fungal diseases. Crop should be ready to harvest 40-50 days after planting. Smaller and younger leaves are usually milder than larger and more mature leaves. Leaves are stronger-flavored as plants begin to bolt.
Noteworthy Characteristics
Brassica juncea, commonly known as Chinese mustard, brown mustard, Indian mustard, or leaf mustard, is an annual herb that is native to southern and eastern Asia. It has been cultivated for food in Europe and Asia for hundreds of years. It has given rise to a diverse range of leaf vegetables, little known in Europe, but popular in eastern Asia, including various Chinese mustard greens and Japanese mizuna.
This plant has been much cultivated in some areas for harvest of spring mustard greens which may be added raw to salads. Older leaves are often boiled before eating. Garden plants typically grow to 1-2’ tall, featuring short, petiolate, elliptic to obovate basal leaves (to 1’ long) with 2-3 lobes per side and upper stem leaves which are much smaller and entire. Leaf edges are toothed, scalloped or frilled. Masses of bright, yellow, 4-petaled flowers mature to 1.5” long, but are not ornamentally attractive.
Although extensively grown as a vegetable for its leaves, this plant is also often grown in some areas for its pungent seeds which are used to flavor many dishes and for its seed oil which is used in Asia for cooking. Pods containing smooth brown seeds mature in summer. Seed is the source of brown mustard.
This plant has also developed a reputation outside the culinary area as a somewhat invasive weed (it is currently included on invasive species lists in Michigan, Florida and Alaska).
Genus name comes from the classical Latin name for cabbage.
Specific epithet means rush-like.
'Japanese Giant Red' is a robust mustard green selection that features purple-red leaves with a sharp, almost garlic-like, delicious mustard flavor. Mature plants will reach up to 1.5' tall with an equal spread.
Problems
Flea beetles, caterpillars, aphids, snails and slugs are the most frequent pests.
Uses
Typically grown in the U.S. from seed in home vegetable gardens. Young plants can be used raw in salads, or steamed or stir-fried when more mature. Colorful-leaved varieties can also be used as cool-season border edgers or container accents.