Potato Growing Guide
Do you know the second most consumed food crop in Kenya after maize?
If you guessed Irish potatoes, you are right!
With an average yield of 7.7 tonnes per hectare, potatoes are grown by more than 800,000 subsistence and commercial farmers in Kenya who collectively generate annual revenues of about Sh50 billion for the country.
This step-by-step guide outlines the process of growing Irish potatoes as outlined below:
Best Conditions for Growing Potatoes
While potatoes do best in sunny environments, this food crop adapts well to a wide range of weather conditions in various parts of Kenya.
Potatoes are tubers or rooting plants that require loose, light and well-drained loamy soil with a pH of 5-7.
Always keep your potato garden/field free from weeds, and rotate different crops to ensure a 3-4 year break from rearing potatoes there.
Potato Varieties to Plant
You need to decide between two main potato varieties before planting: maincrops and earlies.
In comparison, maincrops mature within 135-160 days after planting, are larger in size, and produce higher yields.
Earlies (first and second) mature within 90-110 days, look smaller, and are known to give the best flavor in foods, such as salads.
Go for the earlies if you have a small garden because they will mature fast and take up less space. Maincrops are suitable for larger gardens that can accommodate higher yields.
Preparing Potatoes for Planting
- Select seed potatoes with protruding eyes/buds.
- 1-2 weeks before planting date, expose the seed potatoes to temperatures of 15-20 degrees Celsius to trigger sprouting.
- When the shoots reach a length of roughly 3cm (1in), they are ready for planting.
- 1-2 days before planting date, slice larger potatoes into smaller pieces using a clean knife, with each piece having at least 1-2 eyes or buds. Smaller potatoes are planted whole.
- Pluck out weaker shoots on early potatoes and leave 4 per tuber.
- Air dry the cut potatoes for at least one day before planting date.
Potatoes can be planted in individual planting holes or in narrowly dug trenches. Here are the steps you need to follow:
- Dig a 12cm (5in) deep trench/15cm (6in) holes with a row spacing of 30cm (1 foot)
- Apply a general purpose fertilizer or sprinkle with compost manure
- Place the potato seeds in each trench/hole, with cut facing down.
- Cover the hole/trench with 3-4 inches of soil.
- When sprouts appear 12-16 days after planting, fill the trench/hole with another 3-4 inches of soil, only exposing a few inches of the plants.
- Repeat for up to 6 weeks until the soil covering the hole/trench is 4-5 inches above the ground.
Potato plants require specific nutrients depending on its growth stage as shown in the table below:
|Growth Stage||Required Nutrients||Role|
|Planting||Nitrogen and Potassium||Early growth|
|Phosphate||More tubers and steady growth|
|Zinc and Manganese||Prevents powdery cab and common scab|
|Sulphur||Prevents powdery cab and common scab and increases tuber numbers|
|Tuber Initiation||Phosphate||Stronger growth and more tubers|
|Phosphate and Magnesium||Bigger tubers|
|Zinc and Manganese||Skin finish|
|Calcium||Reduces internal rust spots, improves skin quality, and for drought tolerance|
|Flowering & bulking||Nitrogen, Magnesium & Phosphate||Maintain tuber growth|
|Calcium||Reduces impact of diseases and improves skin finish|
Evidently, potatoes require higher supplies of calcium and magnesium, especially because they are removed in the tubers during harvest.
Magnesium plays a critical role in photosynthesis, produces energy and increases yields, while calcium resists diseases and improves tuber quality.
You can harvest early variety potatoes 2-3 weeks after the flowering process is complete.
Gently dig around the plants to carefully take out bigger potatoes first and leave smaller ones to continue developing. This harvesting method allows potatoes to be fresher and tastier.
If you are harvesting during dry weather, leave the potatoes in the field for 2-3 days without washing them to allow their skins to mature fully for storage, spread them in a cool dry place for curing purposes.
When it comes to maincrop potatoes, leave them underground for at least another 2 weeks before harvesting. Use a fork to lift them carefully, and air dry them for a couple of hours before transporting them for storage in a dark, cool and dry place.
Are you a subsistence or a commercial potato farmer looking forward to boost profits, maximize yields, and improve efficiency?
Feel free to contact Kumea Agriculture for reliable potato growing guidelines and services.