An orange-yellow dye is obtained from the flowers. A useful green manure plant, fixing atmospheric nitrogen.
An important food plant for many caterpillars. It is also a good bee plant, the flowers providing an important source of nectar. The flowers are powerfully scented, even though they are able to pollinate themselves. The plant spreads very freely at the roots.
Requires a well-drained soil in a sunny position. Dislikes shade. Does well on poor soils.
Pre-soak the seed for 24 hours in warm water and then sow in the spring or autumn in situ. The seed usually germinates in 2 - 4 weeks at 15°c. If seed is in short supply, it can be sown in pots in a cold frame. When they are large enough to handle, prick the seedlings out into individual pots and plant them out in late spring or early summer.
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.
The plant is used externally as a local anti-inflammatory compress in all cases of skin inflammation.
All parts of the plant are poisonous, containing cyanogenic glycosides(hydrogen cyanide). In small quantities, hydrogen cyanide has been shown to stimulate respiration and improve digestion, it is also claimed to be of benefit in the treatment of cancer. In excess, however, it can cause respiratory failure and even death. This species is polymorphic for cyanogenic glycosides. The flowers of some forms of the plant contain traces of prussic acid and so the plants can become mildly toxic when flowering. They are completely innocuous when dried.