Tephrosia candida aka White Tephrosia

Tephrosia candida, or white tephrosia, belongs to the pea family, Fabaceae. It comes from the Indian subcontinent. Sources list India, Nepal and Bhutan within its range. It grows in forests and on disturbed ground. These sites include roadsides, fields, riverbanks and steep slopes. Growers plant it in many tropical countries, chiefly in Asia.

This deciduous plant varies from an upright herb to a shrub. It can also form a small tree. Loose branches grow from near its base. Garden sizes reach about 10–11.5 feet [3–3.5 metres] tall. Some plants reach 16.4 feet [5 metres]. Its spread can reach about 10 feet [3 metres]. Sources differ on growth speed, describing it as medium or fast. Insects pollinate its flowers. Gardeners sometimes grow it as an ornamental plant.

It needs warmth and cannot withstand frost. PFAF lists USDA zones 10–12. Daytime temperatures of 20–30°C suit it best. Full sun suits it, though it accepts light shade. It prefers moist soil with good drainage and cannot tolerate waterlogging. Sandy and loamy soils both suit it. It can grow on poor, eroded land and mine waste. Acid soil seems best, though it tolerates a wider pH range. Sources place it in both wet and seasonally dry tropical settings.

Its main value lies in improving soil and supporting crops. It fixes nitrogen and produces leafy growth for green manure. Growers use it to restore worn land and limit soil erosion. Its added organic matter helps soil hold water and drain. It can also raise soil phosphorus and potassium levels. Plantings provide shade, shelter and hedges. Other recorded uses include fuel and soil cover. These uses explain its place in agroforestry rather than food production. PFAF records no known food or medicinal uses.

The plant contains rotenonoids, which pose a poisoning risk. These compounds harm humans and other mammals. They are far more toxic to fish and many insects. People have used ground leaves to kill insects. Reports also describe bark and roots used to poison fish. Do not treat this plant as edible. The sources disagree about its weed potential. PFAF marks it as non-weedy; Useful Tropical Plants flags a risk. The supplied accounts name no specific pests or diseases.