Banana farmers count on unique fertilizer to increase bunch size, shelf life

A fertilizer specifically targeting bananas which were introduced in the country two years ago has recorded impressive uptake among smallholder farmers who praise it for tripling yields and increases the shelf life for ripe bananas thanks to the extra potassium not present in conventional fertilizers.

Dubbed Mavuno Fertilizer, it was introduced by cement maker, Athi River Mining Limited, increases the weight of bunches of tissue culture bananas by up to 10kgs while adding four to five days of extra shelf life for ripe bananas.

Thousands of banana farmers have already switched from DAP fertilizer, which has no potassium in it according to the company. It is mixed to provide nitrogen, phosphorous and potassium in the ratio of 10:3:20 compared to DAP which provides a ratio of 18:46:0.

“Potassium is the key element in bananas it’s why we saw the need to have it in higher quantities in our fertiliser,” said Julius Nyabicha, ARM’s technical officer. The bananas are also sweeter. However, farmers have been using DAP or tea fertilisers. DAP is more suited to maize thanks to its high phosphorous mix, which maize needs to prevent its growth being stunted. Maize develops poor root systems and its lower leaves turn purple if it doesn’t have enough phosphorus.

The Mavuno banana fertiliser is applied on planting and every six months on each stool of bananas. Each stool with three banana cultivars requires 250gms to be effective. However, a banana field extension officer with Africa Harvest still emphasizes the importance of phosphorous fertilisers. “It’s very important for root development,” in the early stages, said Eugenio Kiogora of Africa Harvest.

Besides the fertiliser, success in getting young bananas to thrive to maturity also depends on fighting nematodes with nematicides. “If they invade a field they are hard to control so it’s better to prevent them,” said Kiogora.

The most common nematicides are Bio Nematon by Osho Chemicals or Mocap by Bayer Chemicals, which are not chemicals but fungi, which don’t contaminate other maturing banana fruits when put on young cultivars.
This is important, because bananas lack a defined harvest period and grow continually, which means that applying chemical pesticides on young cultivars in a stool can contaminate banana fruit on an older cultivar.

To use the fungi nematicides 100gms of a product like Mocap is mixed with 20 litres of water and a litre is applied per stool at the base of the root. If banana plants are properly farmed, the Grand 9 tissue culture variety can produce top-level yields, of up to 100kgs of bunch.

Farmers can so far buy the new Mavuno Fertiliser in Kisii, Meru, Kirinyaga, Muranga and North Rift. ARM also produces specialist fertilisers for specific crops like maize, wheat, barley and also for specific soil-types.