Suleiman Njeru started with tomato farming in 2010 but the crop did not yield much and he incurred huge losses due to the harsh humid climate.
A friend advised him to try tree tomatoes, which have a high demand in Runyenjes.
"I was told that the market for tree tomato fruits was huge locally because not many farmers grow the plant,” he says, adding that the main crops grown in Embu county are tea, coffee and vegetables.
Njeru bought the Red Oratia tree tomato seedlings from his friend and planted in a small parcel of land that his parents gave him. He got Sh30,000 from the first harvest which lifted his spirits and he planted more seedlings. Njeru’s first batch of tree tomatoes matured after two years and earned him more than Sh50,000.
This encouraged him to grow more fruits. But he was keen to shorten the period the crop was taking to mature. Besides, Njeru realised that he was spending a lot of money on fertiliser and pesticides.
"The plants also needed a lot of water to enable them bear large fruits and survive especially during dry seasons,” he says.
A friend, who had learned about grafting tree tomato with an indigenous tree known as Muthakwa in Kikuyu and Embu language at Wambugu Agricultural Training Centre in Nyeri, advised Njeru to adopt the skill of grafting.
He collected seeds from the Muthakwa tree from the nearby Kirimiri forest and prepared more than 3,000 seedlings in 2014.
Within a month, he transplanted the Muthakwa tree seedlings, grafted them after two months and six months later, the plants started to bear fruits. Currently, Njeru has 2,000 trees of the fruit.
Unlike other varieties of tree tomato, Muthakwa-grafted tree tomatoes bear fruits all-year round with a single tree producing between 50kg and 85kg in six months. The fruits are picked after every two weeks and can survive for 10 years.
David Gitari, an agricultural extension officer in Embu, says Muthakwa tree tomatoes thrive in fertile, light soil that is rich in organic matter.
He says Muthakwa-grafted variety does not require a lot of water because it has taproot that allows the plant to get nutrients and water underground.
"The ordinary tree tomato plants have shallow root system, which are bettered through grafting,” says Gitari.
"Normally, a tree tomato plant takes two years to bear fruits, but the grafted one matures in nine months. The grafted variety is more resistant to diseases, matures faster, and does well in high altitude as well as drier areas because it acquires favorable traits from indigenous Muthakwa plant,” Gitari says.
Dr Paul Nthakanio, a genetic and biotechnology senior lecturer in Embu University College, says hybrid vigour arises from the crossbreeding of genetically different organisms in plants.
"Due to the vigour, plants are able to grow faster before the pests and diseases accumulate and even before the water becomes limited. This way they are able to evade pest and disease destruction and water shortage hence higher yield. Additionally, a mixture of genes enables other functions to work better such as photosynthesis. When this happens, hybrid plants produce bigger fruits compared to pure ones,” he says.
Njeru receives farmers in his farm daily, who come to learn how to graft Muthakwa-grafted tree tomato, at cost of Sh200 per person.
He sells his tree tomato fruits at Sh100 per kilogramme locally and to individual buyers from Nairobi. “The market is readily available because I am not even able to satisfy demand and this is the reason why I am now coaching other farmers to grow this fruit,” says Njeru.
Besides selling fruits, Njeru also sells grafted tree tomato seedlings at Sh100, and he sells more than 200 seedlings a month.