About 238,540 hectares of potatoes are grown annually in Ghana. Growing potatoes In Ghana has high potential. Potato production has increased in recent years mainly due to growth in population and diversification of crops.
Potato is one of the most important food crop in Ghana. It is cultivated by over 800,000 growers who are mostly small holder. This figure can be increased if production and processing is optimized.
The potato has the capability of providing cheap and nutritionally rich staple food requirements for the country’s fast growing population, especially, since the main staple food, maize, has its yields declining due to a host of factors including increasing soil acidity and changing land use patterns.
Growing Potatoes in Ghana – Ecological Requirements
The most favorable climatic conditions are in areas with annual rainfall of between 850 mm and 1,200 mm, and altitudes of between 1,500m and 2 800m above sea level.
Growing Potatoes in Ghana – Seed Varieties
Some of the seed varieties available are: Ambition, Arizona, Arnova, Sauti, orange flesh, Okumkom, Faara and Santom Pona, Sarpo Mira, Setanta and Orla potatoes
Growing Potatoes in Ghana – Aeroponics
The aeroponic system of cultivation for the production of first generation seed potatoes is carried out in greenhouses, and basically consists of maintaining the roots of the plant in the air and in conditions of total darkness, whereby nutrient-enriched water is sprayed on them periodically. Roots grow in the air, enabling a great exposure to air and avoids the contact of the tubers with soil pathogens. Therefore, the production per plant increases considerably.
Growing Potatoes in Ghana
This increase brings the price of the tuber down substantially.
The system increases productivity, as it is expected that up to 50 tubers per plant can be obtained instead of the three or four achieved using conventional methods. Moreover, it reduces the rate of soil-based diseases such as PLRV; bacterial wilts and it is a more sustainable system as it needs lower inputs of water and fertilizers in precise amount of both items needed by the plant at each phase of its development.
Most agricultural plants need a direct exposure to the sun during the first vegetative development.
Afterwards this direct exposure is no longer relevant. But the aeroponic system ensures a non-stop production cycle. Plant nutrition is supplied in a closed circuit. Consumption is consequently limited to the quantities absorbed by the plants, allowing for substantial water savings.
Because the aeroponic system is a continuous cycle in an enclosed space it reduces the agricultural labour into a series of mechanical routine operational tasks which are carried out daily and throughout the year.
The aeroponic equipment is sheltered within greenhouses hence climate controls within the greenhouse ensure optimal growing conditions, assuring high yields.
The basic local requirements to achieve this are some sunshine and a level area of land not shaded by mountains or high buildings. The area should be accessible by road and have water of suitable quality for agricultural use and, lastly, a constant but small amount of electricity.
Aeroponic growing is considered to be safe and ecologically friendly for producing natural, healthy plants and crops. The main ecological advantages of aeroponics are the conservation of water and energy.
As aeroponics is conducted in air combined with micro – droplets of water, almost any plant can grow to maturity in air with a plentiful supply of oxygen, water and nutrients and since the aeroponic systems because the increased aeration of nutrient solution delivers more oxygen to plant roots, stimulating growth and helping to prevent pathogen formation.
Growing Potatoes in Ghana – Planting
Prepare the land where the potatoes are to be planted. Add compost or well-rotted manure to the soil. Potatoes are commonly grown in hilled rows. This involves digging shallow trenches 60–90 cm apart after the addition of the compost or manure or fertilizer. Space the potato seeds 30 cm apart and cover with 7.5 cm of soil. When the plants reach about 25 cm in height mound the soil up around the stems of the plants so that they are covered up to about half of their height. This protects shallow tubers from turning green from exposure to sunlight. Allow the plants to grow another 25 cm and again mound the soil.
Growing Potatoes in Ghana – Propagation in Potato Cultivation:-
Potato crop is usually cultivated by planting tubers. Purity / quality of the varieties and healthy seed tubers are the primary requirement for successful crop cultivation. However, seed tubers are the costliest input in potato cultivation. The tuber seed should be disease free, well sprouted, 35 to 40 grams each in weight. The physiological age of tuber should be two to three months from the harvest of the crop.
Growing Potatoes in Ghana – Seed Rate, Seed Treatment, Spacing and Planting in Potato Cultivation:-
Generally, seed requirement depends on the cultivar and soil type. In potato cultivation, seed required per hectare is 1,300 to 2,000 kg. Planting season depends on region, climatic conditions and variety of potato. Spacing of seeds is not consistent across the regions because of growing conditions and market needs. Usually, in hilly areas where furrow method is followed, a spacing of 60 cm x 30 cm is maintained where as in plains, ridge plantation method is followed and a spacing of 30 cm is maintained. Ridges distance is kept as 45 cm – 60 cm. reducing the in-row spacing to minimize oversized tuber production may lead to higher quality tubers for fresh markets.
Generally, the major portion of potatoes is planted from April month to early June. It is advised to plant the potatoes when soil temperature is above 7 °c and below 22 °c. While planting the potatoes, make sure the soil has moisture content but not excessively wet. In dry areas, light irrigation should be provided before planting. If high yields and large tubers are expected, a deeper planting depth is considered.
Tubers of seed potatoes should be warmed to 10 °c to 15 °c before handling and cutting to minimize the potential for bruising. Potato seed should be warmed and removed from cold storage 7 to 15 days before planting. Tubers should never be taken from cold storage and planted directly. Whole potato or cuttings of potato can be planted.
Growing Potatoes in Ghana – Irrigation in Potato Cultivation:-
Irrigation is among the most important factors determines the yield and quality of potatoes. The irrigation requirement depends on variety of potatoes, relative humidity, solar radiation, day length, length of growing season, and other environmental factors. However, the seasonal requirement for cultivars in all areas will be at least 500 mm of water.
As much as 750 to 900 mm of water will be required in some specific production areas depending on soil type, weather conditions, and potato cultivar. Water should be applied to the soil frequently in light volumes to maintain the crop with adequate moisture. Irrigation is required throughout all growth stages of the potato crop particularly during tuber initiation and tuber enlargement.
If the crop is not rain fed but irrigated, several methods of irrigation are available. The most common methods of irrigation in potato cultivation are; sprinkler irrigation, furrow irrigation and sub-irrigation. Method of irrigation depends on the geography of the land.
Growing Potatoes in Ghana – Manures and Fertilizers in Potato Cultivation:-
Potato crop requires more nutrients. The requirement of N: P: K ratio should be 120:50:225. Well-decomposed farm yard manure of 25 tonnes/ha (FMY) or equaling garden compost / green manure can be applied in the soil while preparing the land for potato cultivation.
Growing Potatoes in Ghana – Intercultural Operations in Potato Cultivation:-
The Intercultural operations like hand weeding, Earthing up should be carried out to control weeds and to keep the soil loose for proper development of tubers. First weeding should be carried when the plants are about 20 cm high. At the same time, light earthing up should be given to support the plant. Second weeding should be carried after 3 weeks and also earthing up should be done to cover the developing tuber.
All these tasks should be performed carefully without damaging root system of potato and developing tubers. Make sure all exposed tubers are covered with soil as part of inter-cultural operations.
Growing Potatoes in Ghana – Potato Pests and Diseases
The major potato pests include:-
Flea beetles chew small holes in plant leaves and can do serious damage fast if they attack young plants. Control: – Keep flea beetle populations low through crop rotation and by maintaining high soil organic matter.
These tiny insects can transmit virus diseases. They suck juices from the leaves and stems of potato plants, injuring them badly. Control: – Insecticidal soap sprays are an effective control method.
They’re slender, brownish or yellowish white and tunnel into plant roots and tubers, spoiling them.
The major potato diseases include:-
Early blight injures foliage and reduces overall yields. Affected leaves develop small, dark brown spots that often grow in size, and which eventually kill the leaves. Control: – Planting certified seed and mulching with hay can prevent this disease.
Late blight is caused by the downy mildew fungus. The disease first appears as water-soaked areas on the leaves then turn brown and black as the leaf dies. The disease strikes often during cool, wet weather and may spread rapidly if the weather warms up. Plants can die in a severe case. Control: – Plant certified seed and use a potato dust to guard against late blight.
Aphids can spread mosaic viruses, which cause potato leaves to curl and appear almost two-toned (light and dark green).
Growing Potatoes in Ghana – Harvesting
The time potato tubers take to reach maturity is variable and depends on the variety being grown. All tubers should be harvested when the leaves have dried. Harvest the tubers by gently digging them up with a fork or with your hands if the soil is loose enough. Harvesting is easier when the soil is dry. Do not wash the tubers prior to storing.
Growing Potatoes in Ghana – Marketing of Potato: –
For fresh market purpose, they can be transported to local markets. If the crop is grown on large scale, it is important to establish a marketing strategy to sell the produce in bulk.