Large Leather Root (Psoralea macrostachya)

At a glance

Lifecycle: Perennial (hardy)
Exposure: Full sun

Cultivation

Succeeds in an ordinary garden soil. Intolerant of root disturbance. This is not the case, we have successfully transplanted plants that were three years old[K]. This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby.

Propagation

Pre-soak the seed for 24 hours in warm water and then sow in early to mid spring in a greenhouse. Either sow the seed in individual pots or pot up the young seedlings as soon as possible in order to avoid root disturbance. Grow them on in the pots until planting out in their final positions. It is usually impossible to transplant this species without fatal damage to the root. Division in spring. With great care since the plant resents root disturbance. It is virtually impossible to divide this species successfully.

Edible uses

Root - raw, cooked or dried for winter use. Starchy.

Medicinal uses

The plant has been used in the treatment of ulcers and sores.

Material uses

A fibre is obtained from the inner bark of the stem. A fibre is obtained from the root. A yellow dye is obtained from the roots.