Corchorus olitorius aka Jew's Mallow

Corchorus olitorius is in the mallow family, Malvaceae. People call it tossa jute, gunny, and Jew's mallow. Kew gives its native range as the Old World's tropics and subtropics. Other accounts leave its exact place of origin unclear. People grow it for food and fibre in warm regions. It is not native to Britain or Ireland.

This upright herb grows fast to about 11.5 feet [3.5 metres]. It grows as an annual, living for one year. Some accounts describe plants that live for a few years. The stems form many branches and turn a little woody. Shiny leaves grow on stalks along the stems. Small yellow flowers grow in groups where leaves join the stem. They form seed capsules, or pods, with ridges. The dull grey seeds have four faces and a long point. PFAF gives August to October as the time for flowers. It lists October as the month when seeds ripen. Insects pollinate the flowers. The plant can pollinate itself too.

This crop grows best in heat, humid air, and full sun. It grows poorly in shade. It prefers rich soil with plenty of humus that drains well. It can grow in sand, loam, or clay soils. It accepts a broad pH range, from 4.5 to 8.2. Keep the soil moist. Reports differ on how it copes with waterlogged soil. Some say it can cope with very wet ground. Others warn against this. PFAF lists USDA hardiness zones 9–11. Seeds can take time to sprout. A soak in warm water can help.

People eat the leaves and young shoots as vegetables. Young leaves can go into salads. Older leaves need cooking, which makes them thick and slippery. Dried leaves can thicken soups. People can also grind them for storage. PFAF lists seeds as edible too. Both PFAF and Useful Tropical Plants report no known hazards. This does not mean that every use or preparation is safe. People use the leaves in traditional medicine. They use the seeds as laxatives.

The stems yield jute fibre for sacks and paper. Growers cut stems when they flower, then ret them to free the fibre. The many branches can make this work harder. Close spacing cuts down on some branching. In gardens, the plant suits crop beds for leaves or fibre. Its main value comes from these crops, not its looks.