Optimal Conditions for Irish Potatoes Production
Altitude: Potatoes are grown mainly in the high altitude areas between 1,500 and 3,000 meters a.s.l. However, some new varieties can still do well in altitude below 1500 meters a.s.l.
Temperature: Potatoes require an average daily temperature of between 15°C to 18°C. Temperatures above 21°Chave adverse effects on potato growth of potato as it leads to sharp decline in tuberization. There is little or no tuber formation.
The cooler the soil temperature, the more rapid the initiation of tubers and the greater the number of tubers formed. Optimum soil temperature for tuber formation is 15-24°C.
Ways One of avoiding high soil temperatures:
Timely ridging and adequate ridge volumes.
Mulch potato garden with maize stokers to reduce soil temperature. This is done mostly when the potatoes are planted before the onset of rains. This is a common practise among potato irish potatoes smallholder farmers in Kenya.
NB: Moist and cloudy conditions, high temperatures and humidity leads to insect pests, foliar disease and virus epidemics.
SOIL MOISTURE: Potatoes require a good supply of soil moisture to maximize the yields and quality. They require between 400 and 800 mm of rain during the growth period (Otieno et al., 2015). Whenever the roots have inadequate water, consequently the leaves and stems are subjected to moisture stress; the growth rate is reduced affecting yields and quality of tubers.
Ways of enhancing soil moisture content
• Addition of manure to the seed bed
• Cutting furrows along the contours to harvest and conserve surface water
• Deep ploughing to loosen an adequate amount of soils for water storage
• Hilling and earthing up to increase surface water harvesting in the furrows.
Common irish potatoes varieties:
Shangi variety
Shangi variety characteristics include;
High prolific versatile use
About 1m high, upright, broad leaves ,light in color
Abundant flowers
Oval tubers, uniform in grading, white flesh
Medium to deep eye pink pigmentation
Very short dormancy
Matures in 3-4 months
Yields 30,000-40000 kgs/acre
Altitude range 1500-2800m
Tigoni variety
Tigoni variety characteristics include:
Tall variety with upright stem
Produces white flowers and tubers are long oval with smooth skin
Has poor tuber storage and short tuber dormancy
Optimal production altitude 1800-2600m
Maturity period 3-4 months
Tolerant to late blight
Has high dry matter content
Yields 14000-18000 kg/acre
Asante variety
Asante variety characteristics include:
Stems are upright to semi upright of medium height
Tubers are round and have pink smooth skin
Tuber dormancy is short
Optimal production altitude 1800-2600m
Maturity period 3-4 months
Has high dry matter content
Fairly tolerant to blight.
Other varieties include; cont, absolute, Ethiopia. Kenya mpya, purple Gold, etc.
