Altitude range
Potatoes require altitudes of 1500 – 3000 masl

Soil type and conditions
Soils should be deep minimum 30 cm, well-drained, fertile, medium loam, preferably gentle sloping land, on mild slopes, ridges should more or less follow the contour with a small longitudinal slope to allow for drainage

The pH should be 5.5 – 7.5, high soil pH causes scab disease and liming is recommended before planting if pH is below that range. Potato nutrient requirements include: N, P, K, Mg, Ca, S, Zn, Cu, Mn, B

Temperature range
The temperatures should be 20-25oC

Rainfall
The rainfall should be more than 750 mm p.a.

Steps during land preparation
1.    Plough when soil is dry
2.    Plough the farm to appropriate tilth 45cm-50cm deep
3.    Add manure and fertilizers to the soil in the right amounts to provide the required plant nutrients for vigorous crop growth

Certified seeds
Seeds should be obtained from dealers, where they have been well-graded and are uniform in size.

 

Since potato seed is too expensive, growers can use seed stock system

Planting materials should be well-adapted to emerging local climatic and environmental conditions

As an alternative option, establishment of raised beds for rooted cuttings or seed plot system that uses raised beds

Rooted cutting system

A system that involves planting of rooted cuttings on raised beds at 30cm by 30cm which develops into small tubers that can be used for further multiplication for further use as seeds

Seed plot system

A system of multiplying potatoes by planting the seeds on raised beds at 30cm by 30cm and harvesting for use as seeds after 3-4 months

Varieties include

General : Kenya Baraka, Roslin tana, Roslin Gucha, Kerrs Pink, Roslin Eburu (B 53), Desiree, Feldeslohm, Kenya Dhamana, Chaguo, Furaha, Romano, Dutch Robin, Shangi, Pumpernet

Current : Tigoni, Asante, Kenya Karibu, Kenya Mpya, Kenya Sherekea, Shangi, Arka, Kabale from Uganda

Imported varieties : Jelly, Karuso, Connect

Others: Unica, Primera, Rudolf

Planting procedure

Plant at 5-15 cm depth but deeper and 30-40cm for white varieties under warm dry conditions

Place tubers with sprouts facing up

For consumption purposes, plant at a spacing of 75cm x 30 cm between rows and 30-40 cm within rows

Seed rate for tubers is 2-2.5 tons per ha. Seed rate depends on soil fertility status, rainfall availability and tuber use

The larger the seed size, the more the amount required

Make wider ridges or mounds if intercropping with annual crops e.g. maize and legumes

For seed potatoes, plant at a spacing of 15-20cm within rows, at 50kg bags per acre

Minimal water is required during normal vegetative growth of the crop

Irrigate during dry spell without over watering that leads to build-up of fungal diseases and poor aeration

Avoid irregular watering for it causes splitting of the tuber

Avoid weeding after flowering because it predisposes the crop to infections and may injure the tubers.

Add manure and fertilizers to the soil in the right amounts to provide the required plant nutrients for vigorous crop growth.

Rotate after every 4 years with non-root and tuber crops, preferably cereals and legumes to break pest and disease cycle such as carrot and improved fallow either under Crotalaria ocroleuca or Leucaena and brassicas

Earthing up should be done at 2-4 weeks after emergence to; enhance for tuber expansion, control potato weevil and prevent greening.

Potato pests include;

Aphids, White flies, Tuber moth, Nematodes Potato Cyst Nematodes (PCN) and Root knot nematodes, Cutworms, and Leaf minor and thrips

Potato pests

Aphids

white flies

Tuber moth

Nematodes

Notato Cyst Nematodes (PCN)

Cutworms

Trips

Pests control strategies

• Certified seed
• Test for potato cyst nematodes (PCN) on soils before planting
• Integrated Pest Management (IPM), including use of repellents
• Crop rotation to observed closed season for crops in Solanacea familyField sanitation, including removing harvest residues
• Organic pesticides (Bio-T-Plus)

Bacterial diseases included; late and early blight, bacterial wilt, verticillium wilt, soft rot and black scurf.

Viral diseases include; potato leaf roll and yellow virus, common scab, powdery scab and wart

Bacterial diseases

Late blight

Verticillium wilt

Disease management strategies

• Plant; resistant varieties, certified and clean seed
• Conduct bacterial wilt and nematode (PCN) test are crucial before planting
• IPM with enhanced scouting
• Field sanitation/hygiene is more important; clean field, remove of harvest residues plant new fields away from old fields
• Remove diseased plantsDo not use diseased plants in compost
• Crop rotation with non-solanaceaous crops
• Spray with recommended fungicides to control blight under IPM program
• Test for bacterial wilt through KALRO or KEPHIS
  
  

Drying leaves is an indicator of maturity.

Harvest 7-14 days after dehaulming by digging up the tubers carefully using a forked jembe to avoid damaging them

They are then dried for a short period of time in rows before gathering them

Potato will produce up to 40tons per ha  or 16tons per acre with proper management.

Packed potato intended for market are transported using bicycle, pick-up, lorries, depending on destination. The produce should be transported during the coolest part of the day

• Clean soil from the potatoes without bruising the skin
• Overstacking should be avoided during transpotation
• Sorting is done to remove rotten, damaged, malformed and weevil infested potatoes, and debris
• Grading is based on size, shape, colour, weight, maturity, market demand
• Potato is packaged in baskets, sacks, crates, depending on distance of transportation Potatoes in gunny bags/sacks be packaged in 50kg and below

Potato can be processed to make potato Crips and French fries.