MAIZE (Zea mays)
Maize. is the staple food in most farming areas and it is grown under diverse conditions of climate, soils and altitude. Maize production in Kenya takes place on both large scale and small scale farms, however, the bulk of it is from small scale farms. Maize is also an important livestock food both as silage and as crop residue, grain, and is also used industrially for starch and oil extraction.
Maize is produced over a wide range of agro-ecological zones in Kenya. It is grown at all altitudes ranging from sea level at the coast to 2200 m above sea level. However, if planted in very low or high altitudes poor yields are realized.
Rainfall requirements vary with different varieties. In general maize will do well in areas that receive 600-900mm of rain. The rainfall should be evenly distributed during the growing period. For higher yields, the crop should receive enough rain during the first five weeks after sowing and at flowering time. Otherwise any drought at flowering time will interfere with pollination and drastically lower the yields.
The temperature requirements of maize vary with varieties. Cold conditions at high altitude will extend life cycle, whereas high temperatures will expose the crop to much respiration and lower the yields. The optimum temperature for good yields will be 30°C.
Soils for maize production should be fertile alluvial or loam soils. They should be free draining as maize is intolerant of water logging.
Maize does well when grown in rotation with other crops such as groundnuts, beans, cotton and tobacco. It takes considerable fertility out of the soil and thus can only be grown continuously on the richest soils or when heavily fertilized.
Some farmers use their own seed. However, to obtain higher yields, hybrid seed or composite seed should be planted. The main characteristics of these different seeds are outlined below
a) Local seed. Low yielding, usually well sheathed and so more resistant to weevil attack in storage, possibly more palatable to local tastes.
b) Hybrid. Very high yielding, but requiring large quantities of fertilizer. As the hybrid is obtained by crossing two varieties the subsequent crops using saved seed will not have the same characteristics and yields will be much lower. New hybrid seed is therefore required each year.
c) Composite (e.g. Katumani) These are stabilized varieties and new seed is not required each year. If proper selection procedures are followed, farmers can use their seeds selected from their harvests up to three seasons after which fresh seeds are obtained from seed companies.