Mustard’s dark green color makes it a very nutritious leafy vegetable that can be grown year round in many parts of the world. It is probably of Asian origin but has been introduced into tropical lowlands as well as temperate areas where it has naturalized.
Crushed Mustard seeds, mixed with spices, water and vinegar, are used in the production of spicy, brown Mustard eaten as a condiment. Oil is extracted from the seeds (39% oil by dry weight) by rotary, expeller or hydraulic processes. Mustard paste has been used in folk remedies because of the soothing warmth it brings to the skin and the bronchial dilation resulting from its pungent aroma. Studies are ongoing as to the beneficial effect that a cover crop of Mustard seems to have against some soil-born diseases and nematodes.
- Elevation: up to 2000 m (6561 ft)
- Rainfall: 500-4000 mm (20-157 in), extra moist for germination and early growth
- Soil: loamy, well-drained, pH 5.5-6.8
- Temperature: 6o - 37° C (43o - 99° F)
- Day-length sensitivity: neutral Mustard greens grow best and have the mildest taste when planted very early in the growing season.
Seeds should be sown 6.3 mm (0.25 in) deep directly into soil or in flats, germinating in five days. Transplant after 20 days when there are 3-4 true leaves. If leaves will be the main crop, plant seeds 20-40 cm (8-16 in) apart in rows 30-50 cm (12-19 in) apart. A crop raised for the seed oil can be planted closer and not thinned. High temperatures, low soil fertility or water stress encourage early flowering and seed set.
In cool seasons, in as little as 30 days, a crop of peppery-tasting leaves may be cut and re-cut weekly. Only four weeks are needed from bright yellow flowers to seeds on tall branching stems. Because seeds shatter easily, they need to be cut when some are still green, bagged and left to dry before threshing and winnowing. Seeds will remain viable for up to 7 years if kept in a dry, dark, cool place.
Well drained soil will discourage growth of molds that cause dark, water-soaked spots on lower leaves. It is best to clear fields of diseased plants after harvest and allow a long crop rotation between Mustard crops and other brassicas. A microbial insecticide (BT) will kill cabbage worms that feed on the underneath side of leaves.
Mustard is said to stimulate the digestive juices. Young leaves are eaten raw in salads (buds as well). Older leaves can be boiled (changing the cooking water once), steamed, stir-fried or the seeds can be sprouted. Mustard greens and stems can be pickled or dried to eat as a welcome green vegetable in winter. As a dark, green leafy vegetable, Mustard is a good source of vitamins A, C, calcium and iron.