Tomato farmers in Kirinyaga County are adopting safer and more sustainable methods
of controlling destructive crop pests following an intensive county-led training for
farmers.
The training, rolled out across 11 tomato-growing wards, has equipped farmers with
practical skills in Integrated Pest Management (IPM) reducing reliance on harmful
synthetic chemicals while safeguarding farmer health, crop quality and the environment.
The training initiated by Governor Anne Waiguru is being conducted in partnership with
the International Centre of Insect Physiology and Ecology (ICIPE).
One of the training programme is focusing on managing the destructive Tuta absoluta
pest in tomato production. The initiative is emphasizing on biological pest control, farm
sanitation, soil health, and the use of biopesticides instead of excessive chemical
spraying, which has long posed health and environmental risks.
Tuta absoluta is a species of moth known for its devastating effect on tomatoes. It is a
major concern for farmers in tomato growing zones like Kirinyaga as it is said to
contribute over 20% of post-harvest yield losses. The biggest challenge in management
of the pest is its fast development of resistant strains for the larvae and adults. Over the
years farmers have relied on use of agrochemicals to control the pest.
Farmers are being trained on non-chemical control methods, including pheromone traps
that prevent pest reproduction, biopesticides, soil testing and strict farm sanitation.
Pheromone traps are highly specific, eco-friendly tools designed to attract, monitor, or
suppress insect pests by using synthetic scents that mimic natural female mating
pheromones. They are crucial in IPM for early detection, enabling precise, reduced, or
zero-chemical pesticide usage in agriculture, warehouses, and residential areas.
Governor Waiguru said the initiative is part of deliberate county investments aimed at
transforming agriculture through science-led, farmer-centered interventions.
“Kirinyaga is the leading tomato-producing county in Kenya, with annual production
rising significantly in recent years. Through capacity building, promotion of high-yield
varieties and market access, production has increased from 46,000 tonnes in 2017 to
116,000 tonnes today, earning farmers approximately Ksh. 6.9 billion annually,”
Waiguru said.
She noted that as production grows, the county is prioritizing safe farming practices that
protects farmers from chemical exposure and ensure consumers access clean, residue-
free produce.
Speaking during one of the trainings in Nyangati ward, County Executive Committee
Member for Agriculture John Gachara said the training directly addresses the long-
standing problem of over-use of agrochemicals in tomato farming.
“We are training farmers on how to stop using synthetic chemicals, which have been
used excessively and pose serious risks. The goal is to ensure that food coming from
Kirinyaga is safe, while also securing better markets for our produce,” Gachara
mentioned.
He said the county, under the guidance of Governor Waiguru, has partnered with ICIPE
to train 1,000 farmers on the use of biopesticides and integrated pest management,
targeting wards with high tomato production.
“This is part of a wider agricultural transformation programme. Beyond tomatoes, we
have similar initiatives for coffee, rice and other horticultural crops,” Gachara added.
ICIPE Research Officer Peterson Wachira said the County Government played a central
role in identifying the pest challenge and facilitating farmer training through extension
services.
“The Kirinyaga County Government enabled us to train agricultural officers and work
directly with farmers on integrated pest management,” Wachira said, adding that Tuta
absoluta remain one of the pest that causes severe losses in tomato production.
ICIPE also conducted two-season demonstrations, comparing 35 farmers using
integrated pest management with conventional chemical-based farming.
“We proved that it is possible to control Tuta absoluta without spraying harsh chemical.
From trapping to biopesticides and sanitation, the tomatoes never come into contact
with hard chemicals. For the first time, farmers were able to eat clean tomatoes directly
from their farms,” Wachira said.
Farmers say the impact of the training has been immediate.
Lucy Wanjiku, a tomato farmer from Kanyekiine Ward, said the training held in Kiaga
helped farmers reduce losses and cut production costs.
“Using organic methods has reduced diseases, lowered costs and significantly reduced
losses caused by Tuta absoluta. With the traps, our expenses have gone down and
profits have increased. The county has supported us by providing planting inputs and
pest traps,” Wanjiku noted
Stephen Munene, who attended the training at Kithiriti, said adopting organic practices
had improved both yields and income.
“The output is very good compared to chemical fertilizers. This method is leaving me
with better returns,” Munene said.
Another farmer, Njuki Mara from Nyangati Ward, said reducing chemical use had both
economic and health benefits.
“Conventional chemicals are expensive and harmful to our bodies,” Mara said. “When
we fall sick, treatment is even more costly, so these safer methods are better for our
health and our pockets.”
