alexa My trials and triumphs with bacterial wilt and aphids in greenhouse - Daily Nation

My trials and triumphs with bacterial wilt and aphids in greenhouse

Friday July 10 2015

Thirty-five-year-old Vincent Evayo in his

Thirty-five-year-old Vincent Evayo in his capsicum farm in Nandi. While his crop seems to be doing well, the farm has bacterial wilt. ELIZABETH OJINA | NATION  

More by this Author

Jubilee market in Kisumu County is busy as I meet farmer Vincent Evayo selling his produce to traders.

Dressed in a grey stripped T-shirt, a blue trouser and white shoes, the farmer had delivered 36kg of capsicum to a trader, his first harvest this season.

Evayo sells a kilo of capsicum at Sh50, but when demand is high, it can go up to Sh80. He collects his cash from the trader and soon, we hire two motorbike taxis and head to his farm in Nandi County, some 30km away.

The farmer says he prefers to use a motorbike to transport his produce because it is fast, and the capsicum reaches the market undamaged.
About an hour later, we arrive at his quarter-acre farm in Cheptol village in Nandi. The farmer grows the capsicum in a greenhouse.

All looks well, and one may admire his ventures, particularly the greenhouse, but Evayo has had a tough struggle with aphids and bacterial wilt in the structure.


The 35-year-old started the greenhouse project in November 2012 after getting training from Kaimosi Rural Service Programme. Initially, he used to plant capsicum and tomatoes in the open field.

Among the skills he acquired were greenhouse site selection, pest and diseases control, seed selection and soil fumigation.

“Armed with the knowledge, I bought greenhouse materials and constructed the 8 by 25m structure. I used Sh150,000 drawn from my savings to set up the facility, connect drip irrigation system and I bought a 1,000 litre water tank and a generator to pump water from a nearby borehole.”

He, thereafter, planted 680 seedlings of Ana F1 and Prostar F1 tomato varieties in the greenhouse in 2013.

“I harvested about 26 crates of tomatoes for about two months that I sold to traders in markets in Kakamega and Kisumu making Sh91,000 in the season.”

The following season, the farmer switched to capsicum, planting 600 seedlings of Citrine F1 variety. After three months, he started harvesting, ending up with 2,750kg in the four months he harvested. He sold a kilo at Sh80. All went well.

In January, the farmer planted 600 tomato seedlings of Ana F1 variety hoping that the rotation would enable him harvest big. However, trouble set it.

“All my tomatoes were attacked by bacterial wilt and aphids. The crops withered and dropped one by one at the fruiting stage despite applying several pesticides,” said Evayo, who incurred about Sh150,000 in losses.


More trouble awaited him as his borehole, the main source of water for his drip irrigation system, dried.

He uprooted the crops, and replaced them with capsicum, planting in the greenhouse 740 seedlings of California Wonder variety as he hoped the plants will not be attacked by the disease. But about 100 on a single row were again attacked by bacterial wilt and the whole farm aphids.

“I did a lot of spraying to control aphids enabling the crops to survive. But for the bacterial wilt, I uprooted the crops on a single row and the rest survived. I have not had a good experience with aphids and bacterial wilt,” says Evayo, who has used an array of pesticides, including a pepper solution as he desperately sought to save his crops.

The remaining capsicum seem to be flourishing, but he is not yet out of the woods. He fears excessive spraying will lead to resistance and it is affecting the quality of his produce. He has also learned the region’s soil have bacterial wilt, which means more losses may be in the offing.

Evayo believes his harvest would have been more were it not for aphids and bacterial wilt.

Prof Mathews Dida, a lecturer at Maseno University’s Department of Agriculture, says aphids and bacterial wilt are common in greenhouses, but the former can easily be controlled using pesticides.

“Another way of dealing with aphids is by use of biological means. You can introduce insects that feed on the aphids but not necessarily harm the capsicum crops or use sticky traps. This will prevent the use of chemicals but it needs technical knowhow,” says Prof Dida.

Also one should maintain high standards of hygiene in the structure.

“One can have specific clothing gear like overcoats and gumboots which they wear and leave in the greenhouse. The structures are very sensitive,” says Prof Dida.

He adds bacterial wilt is soil-borne. The best way to manage it is through a process called solarisation. “The farmer should take the soil, cover it in clear polythene material under the sun for some days. The sun would heat the soil, thus, bacteria causing the wilt will eventually die. A soil analysis will help identify the soil early.”

Simlaw Seeds Chief Research officer Robert Musyoka says to eliminate aphids, one should not wait until there is an outbreak. “Spray the greenhouse before planting, in case there are any aphids eggs they will die. The best chemical to use is thunder.”