This archive report was first published on 16 November 2019.
As the harvesting season comes to a close, many farmers in Kenya are looking for alternative crops to plant for an effective rotational programme. One such crop that has gained popularity in recent years is canola, a plant bred from rapeseed that offers a range of benefits for farmers.
Canola is a member of the brassica family and grows to a height of three to five feet, producing small, yellow flowers that mature into seeds that produce canola oil and meal. The demand for canola oil, which has low saturated fats, is high, making the crop highly marketable.
According to experts, canola does well in well-distributed rainfall and can be grown in a wide range of soils that are well-drained and have moderate soil fertility. The crop requires nitrogen and phosphorus as the primary nutrient, but a successful fertiliser programme is based on the knowledge of the soil nutrient level and requirements.
Proper land preparation is essential for canola, as it helps control weeds before planting. The vegetative nature of the crop normally smothers weeds, but broadcasting or shallow drilling can also be used to plant the seeds. For optimum growth, the plant requires temperatures between 15-20°C, but low temperatures are usually a prerequisite to flowering.
Canola is primarily grown under rain-fed irrigation, but timely planting is ideal as moisture stress during flowering leads to reduced yield. In dry areas, irrigation can also be done to obtain optimum yields. The crop has a large taproot, which cracks into the soil, improving drainage and controlling disease during decomposition of root residues.
Once canola is established, it does not require much attention other than spraying to control pests and diseases when necessary. However, the crop is affected by pests and diseases such as diamond back moth, which can be controlled by adopting integrated pest and disease management.
Windbreakers like agroforestry trees or maize crop should be planted on the edge of the farm to minimise seed loss. Harvesting is done when the crop appears brownish, and the majority of the seeds are in the firm dough stage with moisture content of about 25-45 per cent. Before harvesting, the crop should be well-dried to ensure smooth harvest, which can be done using combine harvesters that also thresh the seeds.
Harvested seeds should be dried or kept cool in a storage room that is well-aerated. While seeds are used to extract oil, the cake makes quality livestock feed ingredient. The canola meal is also used as a high-quality organic fertiliser.
Published on November 16, 2019.
