Farmers in arid Makueni have seen the light in farming high-value fruits thanks to half-moons dug around papaya trees to catch and store run-off rainwater and nutrients.
Half-moons or water bunds, also known as ‘smiles’ because of their shape, are shallow semi-circular structures dug to capture rainwater and topsoil that would have been washed away in arid dry soils.
Thanks to extension officers from the Center for Training and Integrated Research in ASAL Development (CETRAD), Justus Mbiti has been able to harvest rainwater using water bunds which he uses to grow papayas and bananas.
“Previously, nothing ever grew well enough on my farm. I would never have thought that I would be able to grow papayas, ” Justus informed.
The young farmer has about 500 papaya trees and 200 bananas on an acre of his land in Kikumini village.
He earns Sh350,000 from his pawpaws annually, and what he describes as everyday cash from his bananas, most of which he uses for his family’s consumption.
Water bunds measure one to three meters wide and are 30-50cm deep. They are dug with the ‘closed’ side of their smile facing downhill to trap and slowly release rainwater and nutrients underground where they can be retrieved by plants and trees when needed.
Research has shown that in two years, farmers in arid areas lose on average 25.7 tons of soil per hectare if they fail to protect their soils. This goes down to just 4 tons of soil per hectare when utilising water bunds. Water bunds also capture up to 79 per cent of rainwater that was previously lost.
“Within the half moon, we advise farmers to apply manure and mulch to help their soil retain the maximum amount of moisture. Ideally, they should also grow a few trees such as yellowwood whose leaves are an excellent source of soil nutrients, and grevillea whose leaves are used for animal feed and when mature can be cut down for expensive hardwood. They are also windbreakers that avoid soil erosion,” explained Wilson Arusei, a CETRAD trainer.
Doing this also quickens the fruiting and ensures the fruits attain maximum weight.
Read more:
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