Potatoes are generally cultivated on the same farm land year after year, with a few farmers rotating potato with other crops such as maize, cabbage, wheat among others. Stubble cleaning is required before preparing the land for planting. However, most farmers simply burn the stubble or uproot crop residuals by hand.
Manual tillage of land using hoes, animal driven ploughs, and other rudimentary tools is still practiced by potato farmers in Sub-Saharan Africa. Those who use the tractor to plough their land, often do so with disc ploughs. Tillage by hand or with a disc plough is both inadequate, as they tend to turn the soil at a very shallow depth. Manual tillage, for example, seldom exceeds a depth of 10-15cm while disc ploughs reach a maximum depth of 20cm. Disc ploughs and animal driven ploughs leave big clods on the land, which makes soil seedbed preparation difficult. In addition, such fields do not facilitate the development of young plants and tuber development.
Most smallholders undertake seedbed preparation by hand. Larger farms rent tractor driven ridgers. Due to the poor tillage described earlier, disc harrows are unable to adequately refine the soils and prepare seedbeds. So farmers tend to plant the potatoes between the clods and break them up later while cultivating the land. This practice results in uneven and poor germination, and limits vigorous tuber formation.
FERTILIZER / SOIL FERTILITY
The fertilizer application is mainly done by hand, utilizing hired labor in most instances. Only a few farms apply fertilizer by tractor-mounted spreaders.
PLANTING / SEED POTATO TUBERS
Planting is done manually by making holes with a hoe and covering the tubers with soil. As the plants sprout and grow, ridges are then formed by a hoe. But the shallow and narrow ridges hinder tuber development. The process is also very labor intensive. Farmers with larger plots rent tractors that pull the ridgers. In such cases, initial steps are taken to mark the rows, place the seed potatoes in the marked rows by hand before the ridger covers the tubers with soil forming smaller ridges.
CULTIVATION / WEED CONTROL
Cultivation and weed control is mainly carried out by hand. Weeding and hilling are performed using exclusively forks and hoes. Farmers also hire labor for this. Large commercial farms apply herbicides and use tractor mounted ridgers. A few service providers having ridgers cannot make use of the equipment for cultivation because they have no access to the type of tires required to drive in between the rows. This is also indicative of the potential lack of spare parts to ensure proper maintenance of equipment.
If crop protection measures are applied, small-scale farmers mainly do this with hand-driven knapsack sprayers. Most small holders own such a knapsack. One limitation with the use of this sprayer is the difficulty to keep an appropriate application rate through the operation, especially on larger plots. Most farmers furthermore, do not know what nozzle sizes to use for particular chemicals at different times of spraying.
The majority of potato farms harvest the potatoes manually with a hoe and/or fork “jembe”, which results in significant damages and losses of potatoes. Damage caused by casual labor and harvesting tools represents 7.4% of on-farm losses. Farmers also harvest immature potatoes for different reasons. In Kenya, the early harvesting is practiced because farmers want to enjoy higher prices, which occur before the peak of the season. Harvesting is labor intensive and the use of inappropriate tools results in damage and poor quality of tubers. Currently, there are no known service providers in Kenya, from whom farmers can rent harvesting machines.
Seed Potatoes Most farmers do not have adequate storage facilities for seed potatoes. Some potato seed tubers are stored at home, until planting time. In Kenya, seed potatoes are generally stored on the floors of farmhouses and in round huts made of mud bricks and straw constructions. High losses occur because of diseases (rot) and pests (rodents) attack. Some small to medium scale seed potato producing farmers constructed diffused light stores. They constitute a minimum of 10% of the farmers in Kenya. A far less percentage that is large commercial farms has their own cold stores for the storage of seed potatoes. Some donor-supported projects have supported the construction of diffused light seed potato stores and are used then, but those remain inaccessible to the majority of farmers.Ware Potatoes
The greater part of smallholder produced potatoes in Kenya are sold directly on the field to merchants. Storage of ware potatoes by individual farmers is virtually unknown in Kenya, as nearly all are sold immediately after harvest.
Seed Potatoes Irrigation ensures that plants have access to appropriate levels of moisture during the different stages of growth, tuber formation, and development. Potatoes are largely cultivated under rain fed conditions in Kenya. Farmers mainly do not practice any form of supplementary irrigation. Thus, risk of lower yields due to weather failures is high. In Kenya, it is mainly in Meru County that farmers use irrigation. About 20% of farmers in this county use furrow irrigation, even though there is a much higher potential. This gap points to some untold challenges with availability and access to irrigation for potato farming in Kenya.
2 For the farm economics section focus group discussions were conducted. Definition: A small group of people whose response to something is studied to determine the response that can be expected from a larger population.