Mitoo (slenderleaf in English) is an annual or perennial herb in the legume family (Fabaceae) and is native to tropical Africa. The word “mitoo” comes from the Luo language and refers to Croatalaria brevidens and C. ochroleuca, both of which have a lower degree of toxicity than many other species of Crotalaria and are therefore suitable for human consumption. The two species differ in terms of both taste and the size of their leaves: C. brevidens is more bitter and has smaller leaves than C. ochroleuca (10×2 centimeters versus 13×3 cm). The leaves, which have a slightly to very bitter taste, are simple or compound with three leaflets. The yellow flowers become tough-skinned, inflated seedpods, which contain 5-50 seeds (depending on the species). The seeds are kidney-shaped and their color ranges from olive green to yellow-orange or brown. Mitoo grows spontaneously among bushes, in the forest (often near termite mounds), in pastures, and in cultivated fields. It is occasionally cultivated on a small scale (sown during the rainy season). In several rural areas of Nakuru County, including Molo and the mountainous areas of the Naivasha district, women familiar with this species collect young leaves and shoots that grow wild at the edges of fields or forests bordering the villages. Harvest takes place about 8 weeks after the plant has sprouted.
Mitoo leaves and shoots are prepared similarly to other traditional leafy vegetables. Because of its decidedly bitter taste and mucilaginous consistency, mitoo is consumed in small quantities and often combined with other vegetables including murere (Corchorus olitorius). Together with some ugali, mitoo often accompanies stewed meat. In the rural areas of Nakuru County (and more generally in Western Kenya), women soak the previously boiled leaves and sprouts in cow’s milk or buttermilk (mala), leaving them to ferment for 3 days. This improves the flavor of the vegetable (reducing the bitter taste) and preserves it for a long time, after which the leaves can be fried or combined with soups and stews.
In Central and Western Kenya, the consumption of leafy vegetables (especially wild and bitter herbs) including mitoo is particularly important among older women. They are among the few people holding the necessary knowledge to collect and prepare these products. The preference for these plants plays an important role in their conservation. In addition to its taste, women appreciate mitoo for its slimy and mucilaginous consistency. This characteristic is associated with various healing properties including the lubrication of limbs and the ability to ease labor. Mitoo also plays an important ecological role within the local agricultural systems: Being a legume, it fixes nitrogen in the soil and ensures an excellent fodder source for livestock. Mitoo harvesting is managed almost exclusively by women and is for domestic needs. Only surpluses are sold, with sale taking place mainly in the local markets of rural areas.
Mitoo consumption is limited due to several factors. On one hand, the available quantity is reducing due to prolonged drought periods and its cultivation is no longer common in Nakuru County. On the other hand, the change in eating habits among younger people, as well as their migration to urban centers, means that the knowledge and practices linked to this traditional plant and no longer passed on.