Tephrosia purpurea (Swahili: kibaazi, kibazi, mibaazi, mtupa, utupa wa kibaazi, utupa wa kingindo, utupa wa mrima) is a multipurpose legume tree with strong insecticidal properties. It grows to a height of two meters within the first year of planting.
Before planting Tephrosia seeds, soak them for 24 hours (to ensure better germination, up to 90%). Plant the soaked seeds 1meter apart. 35,000 seeds per hectare will give the greatest leaf yield. When you harvest leaves carefully, the plant will continue to produce. It can grow to height of 3 meters. ECHO staff member Beth Doerr has experience with Tephrosia in Malawi. She found that it establishes easily and quickly, and has lots of biomass. She planted trees 0.6 meters apart, and after 7 months the plants had formed a living wall.
Tephrosia leaves can be used to make an insecticide. Emmanuel Soko is an extensionist working in TZ. He advises:
Take fresh leaves and dry them under the sun. Grind the dried leaves into a powder. Mix 100g powder with 100kg of maize to control both maize weevils and the larger grain borer; mix 100g of powder with 100kg of beans to control bean bruchids. The chemical is effective for up to three months. After that time, the process must be repeated. You can also wash animals in a Tephrosia solution to control ticks, lice and flies. [To make it,] pound fresh leaves and add 5x the volume in water.
To make a liquid insecticide, soak fresh ground leaves (5:1 with water) overnight, or boil for 30 minutes. Then add soap (to make the liquid ‘stick’). Use it in the garden to control “termites, ants, beetles, aphids, cutworms, various bugs and weevils, stalk borers, flies”. As an alternative, crush the leaves using a rock and a plastic feed sack, soak for two hours, filter, and use in a sprayer. Use the spray within 24 hours. Save the crushed leaves to make a second batch, as some effective chemicals will remain. Use 20g leaves to 100ml water; the amount of leaves should equal the weight of an empty 300ml coke bottle, and then add 7 coke bottles full of water. The compound leaves contain the highest concentration of rotenoids. The active ingredients break down in the sun, so the extract should be reapplied at least every 7 days.
Tephrosia is a helpful mulch against termites, who won’t eat it. The flowers apparently don’t have the insecticidal characteristics of the leaves, but during flowering, a leaf extract may be sprayed on the flowers to good result.
Some reports from a village in Zambia indicated that people became ill after eating fish that had been poisoned with tephrosia extract. Traditionally tephrosia has been used by Samburu and Maasai pastoralists in Kenya to rid their livestock of ticks. It is also used to treat diarrhea in chickens.
For more information, see the following documents on www.ECHOcommunity:
- EDN 65, “Tephrosia Fallow Management in Cameroon” by Stefan Cherry, Cameroon"
- Amaranth to Zai Holes, Chapter 8 (Plant Protection Treatments)
- See also “Fish Bean: ECHO Plant Information Sheet”