Why I’ll never leave my sweet potatoes

Friday July 31 2015
Potato px

Karungo wa Thangwa when he harvested sweet potatoes on his farm in Ngewa, Githunguri, in Kiambu County. ERIC WAINAINA |


Smoke billows from one of the farms in the sloppy Ngewa Village in Githunguri, Kiambu.

We draw closer and find Karungo wa Thangwa, the area MCA, boiling some of the sweet potatoes about 20 young men are still harvesting.

He will later rush to the county assembly in Kiambu Town for the afternoon sessions.

Some of the young men are busy ferrying the potatoes to a central point, where a buyer is waiting as others continue harvesting them.

“I was in Kirinyaga and saw how buyers from Nairobi and other towns were scrambling for sweet potatoes. The farm price was good and I decided to try it,” Thangwa says.

He leased land and planted the Bungoma type, a conventional type of sweet potato, in less than an acre of land. The red potatoes are said to be rich in vitamins. The crop is popular because it grows faster and has more yields.


“I bought the cuttings in Kerugoya for Sh5, 000 and planted them,” says the former broadcaster.

After three months, Thangwa, with the help of farmers in Kirinyaga, got a buyer and struck a deal. He would sell all the sweet potatoes on wholesale. He sold the 70 bags he had harvested for Sh3,500 each.

Stephen Mureithi, the principal at Waruhiu Agricultural Centre in Githunguri, says if well cultivated, an acre can produce up to 40 tonnes of sweet potatoes within three to four months. The crop, he says, has minimal expenses in form of inputs.

“You do not even use manure or pesticides. You only need to follow the expert’s advice when planting. You must also water and prune,” Mureithi says noting the demand for sweet potatoes in the county is growing fast.


“Many companies are now adding value to the potatoes, including fortifying maize and wheat flours.”

After the success of the first attempt, Thangwa has decided to go full scale. He says he’ll plant the potatoes on at least one-and-a-half acres. “I am working with experts to ensure I do everything right,” he says.

“I am targeting not less that Sh450, 000 in December when I will be making my second harvest.”

“It’s a venture I can encourage the youth to get into. It’s not tiresome or time consuming, does not require a huge piece of land or too much capital and returns as also good,” he says.

“The lowest a bag can fetch is Sh2, 500 and the market is ever available,” Thangwa told Seeds of Gold.

He adds: “There is a ready market, especially in Nairobi, where traders are currently buying the potatoes from Kirinyaga and western Kenya. They would like a source that is close to their business to reduce the costs of transportation.”

The other major advantage of sweet potatoes is that they thrive in a variety of soil types and climatic conditions.

Kakamega, Bungoma, Busia, Homa Bay, Rachuonyo and Kisii counties are the main producers of sweet potatoes while central Kenya produces only a small fraction.

Thangwa lamented that farmers are losing money due to unethical packaging. “Some buyers have improvised bags to take close to double what normal bags take,” he said.

“If the government intervenes, the business can be more profitable,” says Thangwa.

Sweet potatoes are in the league of the so-called “orphan crops”, alongside cassava and millet. Many have abandoned these crops because they are considered the poor man’s food. However, development experts say the best way to transform African farming is to return to these crops.

They say for sub-Saharan Africa to benefit from advances in agricultural productivity, investments in “orphan crops” will be key to strengthening the livelihoods of poor farmers and improving nutrition.

And sweet potato farming is set to expand even further with the introduction of value addition.

Lillian Jeptanui, a horticultural expert at Egerton University, says processing sweet potatoes to make flour and crisps will help farmers get more returns.


“They can also be vacuum sealed and frozen to lengthen the shelf-life. And to ensure high-quality flour, processors can add nutritional ingredients such as amaranth flour, which would supplement the nutrients,” Lilian says.

“The yellow flour is very marketable. It is used for making chapattis, cakes and soup. Yet, only a handful of farmers are into value-addition,” says Lilian.

“Just like other crops, the price of sweet potatoes drops significantly during the peak seasons, the more reason why farmers should preserve their produce for a rainy day.”

The sweet potato tubers can also be boiled and eaten, blended and processed to make natural juice.

Value addition is expected to revolutionise sweet potato even further.