Eriosema kraussianum Seeds | Eriosema
LATIN NAME: Eriosema kraussianum
COMMON NAME: Eriosema
Plant Profile
Eriosema is a low, clump-forming perennial of the pea family, thirty to sixty centimetres tall, with narrow leaves covered in fine silky hairs and small orange-yellow flowers carried in short spikes. The name refers to that woolly covering, and it gives the whole plant a soft, grey-green cast that stands out against the coarse grasses around it.
It grows in the grasslands of eastern South Africa, in full sun on well-drained, often stony ground that is burnt in winter and soaked in summer. Beneath the surface it makes a woody tuber, which lets it survive both the fire and the drought, and which pushes new shoots up within days of the first rains.
Science & Biotechnology
Eriosema is a large genus of some hundred and fifty species, mostly African, and it belongs to the phaseoloid group of legumes alongside pigeon pea and cowpea. The genus is known for mixed reproductive strategies: some species set normal aerial pods, while others bury their fruit in the soil and ripen it underground.
The tuber is the chemical focus. Eriosema kraussianum has been examined for isoflavonoids and for the compounds behind its traditional use as a tonic, and the results sit within the wider pattern of legume root chemistry, where prenylated isoflavones are common and often biologically active.
Uses & Benefits
Traditional practice in KwaZulu-Natal uses the tuber, usually as a decoction, for a range of complaints, and the plant is sold in local medicine markets. It is not a commercial crop and has no significant fodder value, since the foliage is sparse and tough.
In the garden it is a plant for a grassland bed or a dry bank, where its silky leaves and small pea flowers fit among other South African perennials. It needs full sun and sharp drainage, and it disappears underground in the dry season, which is a habit worth planning around before you plant it at the front of a border. It also associates well with other grassland plants such as agapanthus and kniphofia, whose coarse leaves hide its own die-back.
Growing from Seed
Scarify the seed lightly and soak it overnight in warm water, then sow into a gritty mix at twenty to twenty-five degrees. Germination is usually two to four weeks, and fresh seed gives the best percentage; old seed may need a second scarification.
The seedling makes a taproot quickly, so use a deep pot and move it only once. Grow it in full sun for two seasons, keeping it almost dry in winter, then plant out into a raised bed or a bank with coarse soil. Mark the spot, since the plant dies back to the tuber and can be lost to a hoe.
Our Take
A modest grassland perennial with a fire-proof tuber and a quiet charm. It needs sun, drainage and a label so you do not dig it up by accident. Pick the spot once and leave it there.
Related Reading
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