Potatoes

INTRODUCTION

Potato is locally referred as Walu (Kikuyu), Kiazi (swahili), Egiasi, Mbatata and Enkwashei. Potato originated in the highlands of South America, where it has been consumed for more than 8000 years. Spanish explorers brought the plant to Europe in the late 16th century and later to Africa in 19th century. Nearly all of Kenya’s potatoes are consumed locally. Potato is relished by the rural people who grow them and also by higher-income urban dwellers. In Kenya it is considered a high quality and prestigious food item.

PRODUCTION

Varieties Kenya Baraka, Feldelslohn, Annet, Roslin Tana/Gucha/Ruaka/Eburu, Cardinal, Pimpernel, Tigoni, Nyayo
Seed Rate 1.5 to 4.0 t/ha
Fertilizer Rate 95 to 140 kg N (nitrogen)/ha, 35 kg P (phosphorus)/ha, 125 to 170 kg K (potassium) per hectare.
Planting Spacing Rows: 75-100 cm apart with row spacing of 30 to 40 cm and population of 25 to 44,000 plants per ha)
Husbandry Potato is normally propagated vegetatively by small (40 to 100 g) tubers, called ‘seed tubers’ or ‘seed potatoes’. It can also be propagated by pieces of tuber (‘seed pieces’) or by true seed. Planting early in the rainy season is best. Planted at a depth of 5 to 15 cm. Earthing up or hilling is carried out to control weeds and to avoid greening of the tubers.
Pest & Diseases Pest Name Symptoms Control
Root-knot nematodes Stunting, yellowing of leaves and a tendency to wilt Bio-fumigation and crop rotation.
Bacterial wilt Wilting without yellowing. Bio fumigation, use resistant varieties.
Maturity Duration 3 to 4.5 months
Climatic Conditions Potato requires well-distributed rainfall of 500 to 750 mm and optimum day temperatures are within the range of 20 to 25°C. Cultivation is concentrated in highland areas from 1200 to 3000 m above sea level. Potato is tolerant to a rather wide variety of soils, except heavy, waterlogged clays. Good drainage is of great importance and a soil pH is between 4.8 and 6.
Harvesting Time of harvesting of potato varies with cultivar, cultural practices, climate and price. Tubers harvested while still immature tend to have low dry matter content and to suffer more skin damage, resulting in easier infection by fungal and bacterial pathogens. Late blight attack may also be a reason for early harvesting. The harvesting operation involves destroying the aboveground parts (haulm), lifting and collecting the tubers. A general practice to avoid excess mechanical damage to tubers at harvesting is to cut the tops 10 to 14 days before lifting the potatoes to give them time to develop matured and hardened skins. Harvesting should not be done during or immediately after rain.
Post harvesting After harvesting it is advantageous to allow the tubers to dry in heaps for about 1 to 2 weeks at 10 to 20°C (or in cold store) under high humidity before further handling. During this time the skin hardens, wounds heal, adhering soil dries and disease symptoms become more visible, which facilitates the removal of the infected tubers. Grading should not be started before the curing and hardening have taken place. Potato tubers are usually delivered into stores in bags, baskets or crates.
Growing Regions Nyandarua, Nakuru, Meru.
Expected yields 20 – 35 tons per hectare

PROCESSING

Processing Potatoes are shred and dried into chips and crisps.

MARKETING

Place Mostly marketed locally.
Price Kshs. 20 -55 per kg

CONSUMPTION

Products and uses Potato Chips, Potato Crisps
Nutritional value – per 100 g / % Daily Values Energy: 93.0 / 5%; Carbohydrates: 21.2 / 7%; Protein: 2.5 / 5%; Phosphorus: 70.0 / 7%; Potassium: 535.0 / 15%.

FACTS & FIGURES

Potato is consumed at an average rate of almost 25 kg per capita a year.

BUSINESS CASE

Income Per Hectare: Kshs 400,000 (20,000kgs * 20/-)Cost per Hectare: Kshs. 160,000 (40% of Income).

NET:    Kshs. 240,000 (60% of Income).

Break Even Yield (Where Cost=Income): = 8000 kgs per hectare.

Income Frequency: Twice per year.