How to grow onions in Kenya: Step by Step Process

Onions are an important ingredient in many Kenyan dishes and are a popular cash crop for farmers. However, growing onions can be a daunting task, especially for first-time farmers. In this article, we will provide a comprehensive guide on how to grow onions in Kenya, covering everything from soil preparation and planting to pest and disease control and harvesting.

Onion Soil Preparation in Kenya

Before planting onions, it is important to prepare the soil properly. Onions grow best in well-drained soil that is rich in organic matter. The soil should be worked to a depth of at least 20 cm to allow for good root development. Remove any stones, weeds, or debris from the soil to ensure that the onion bulbs have enough room to grow.

Onion Fertilizer Application in Kenya

Onions require a steady supply of nutrients to grow well. It is important to fertilize the soil before planting. Use a balanced fertilizer such as 17:17:17 or 23:23:0 at a rate of 150-200 kg per acre. After planting, top-dress the onions with nitrogen-rich fertilizers such as CAN or Urea at a rate of 100 kg per acre. Repeat the top-dressing 3-4 times during the growing season.

Transplanting Onions in Kenya

Onions are usually planted in rows with a spacing of 10-15 cm between plants and 30-40 cm between rows. Plant the onions at a depth of 2-3 cm, with the pointed end facing up. Onions can be planted either by seed or by transplanting seedlings. If planting by seed, sow the seeds in a nursery bed and transplant the seedlings when they are 8-10 cm tall. If transplanting, make sure to handle the seedlings carefully to avoid damaging the roots.

Onion Irrigation in Kenya

Onions require regular watering to grow well. In Kenya, onions are usually grown during the dry season, so it is important to ensure that the plants receive enough water. Irrigate the onions immediately after planting and then every 3-4 days depending on the weather conditions. Avoid over-watering as this can lead to waterlogging and rot.

Onion Pest and Disease Control in Kenya

Onions are susceptible to a variety of pests and diseases. The most common pests include thrips, onion maggots, and aphids. The most common diseases include purple blotch and downy mildew. To control pests and diseases, it is important to spray the onions with appropriate pesticides. Mix 12g (1 tablespoon) of Control with 20L of water in a knapsack and spray the onion plants every 14 days. To control thrips, use both Nimbecidine and Final Flight. Mix 30ml Nimbecidine with 20L of water in a knapsack and spray the plants 15 days after planting. Repeat every 15-20 days. Mix 4g Final Flight with 20L of water in a knapsack and spray when you see thrips. Repeat every 10 days.

Onion Harvesting and storage in Kenya

Harvesting onions is an exciting time, as it marks the end of a successful growing season. When the soil at the base of the plants starts to crack, and 50-75% of the leaves have turned yellow and fallen over, it’s time to harvest. Bend over the rest of the tops and leave the onions on the soil surface to begin to cure.

Leave the onions in the sun for 10-14 days, until the neck of the bulb is very dry. Cut the leaves, leaving about 3.5 cm from the stem, and take off the roots. Grade the onions according to shape, size, colour and quality. Store the well-cured onion bulbs for up to 6 months in a clean, cool, dark and dry place. Store them in net bags, not sacks.

Onion Record-keeping in Kenya

Keeping good crop-growing records will help you run your business better. Keep records on field history, problems faced, major activities like planting, spraying, diseases, and harvesting. This information will help you to track your progress and make informed decisions in the future.


Growing onions in Kenya is a profitable venture that requires careful planning and execution. With the right techniques and best practices, farmers can maximize their yield and profits. By selecting the right variety, preparing the soil well, planting at the right time, proper irrigation and fertilization, controlling pests and diseases, and proper harvesting and storage, farmers can ensure the success of their onion farming enterprise. With the tips and strategies provided in this article, we hope to empower farmers to take their onion farming to the next level.

Joseph Boit
Show full profile Joseph Boit

Joseph is a social entrepreneur with a curious mind and a love for farming. Big dreamer and a technology enthusiast.

1 Comment
  1. Am interested in onion farming advise please

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