Maruku (Dioscorea bulbifera) is a climbing yam that bears its “tubers” (actually bulbils) along the stems. It grows up to a height of about 10 meeres and produces yams only once a year, starting from around March and reaching maturity around August or September. After the yams mature, the plant dies back and remains dormant in the ground until the next season, when it sprouts again. The yams have a butterfly shape and are yellow inside with a taste close to the white potatoes when cooked. The outer skin is grey with a thin green layer underneath. Maruku is often eaten after being roasted in the ashes of a fire and then peeled.
The product is associated with the tropical rainforest region in Western Kenya. It is still being grown by few farmers in the district of Emuhaya and surrounding areas within Vihiga County, but in small quantities. It is mainly cultivated for personal or family use, and maruku is only found for sale commercially rarely, when there are plentiful seasons and excess yams. The Abanyole sub-tribe of the Luyha people in western Kenya consider maruku a treatment for the measles.
Maruku is disappearing in most gardens as farmers adopt more monocropping. About 20 years ago it could be found sold in markets Emuhaya District. It is considered a delicacy and liked by many old people who still it to grow. Continuous clearing of natural forests and the lack of knowledge transfer from the elderly to the younger generations has contributed to reduced farm diversity and disappearance of crops such as maruku. Very few gardens owned by the elderly still intercrop it within their banana plantations.