Growing macadamia in Kenya is becoming increasingly popular due to the high demand for the nut both locally and internationally. The nut is known for its numerous health benefits and delicious taste, making it a highly sought-after commodity in the market. However, to achieve a successful macadamia harvest, farmers need to adhere to specific guidelines that ensure the trees grow and produce nuts optimally.
Macadamia trees require specific ecological conditions to thrive, including optimum temperature, rainfall, and soil pH. Farmers need to consider these conditions when planting macadamia trees to ensure they grow and produce nuts optimally. Additionally, farmers need to take proper care of the trees, including regular irrigation, mulching, and pest control measures, to ensure the trees remain healthy and productive.
In this article, we will provide a comprehensive guide on how to plant and care for macadamia trees in Kenya. We will cover topics such as suitable ecological conditions, planting and spacing, soil preparation, irrigation, fertilization, and pest and disease control measures. By following these guidelines, farmers can achieve a successful macadamia harvest and reap the benefits of this lucrative crop.
Climate and Soil Requirements
Macadamia nuts thrive in a subtropical climate with moderate rainfall and cool temperatures. The ideal temperature range for growing macadamia trees is between 18°C to 25°C. The trees require a minimum of 800mm to 1200mm of rainfall per year, which should be well distributed throughout the year. However, too much rainfall can lead to root rot, so well-drained soils are essential.
Macadamia trees grow best in deep, fertile, and well-drained soils with a pH range of 5.0 to 6.5. The soil should be rich in organic matter, and the trees require adequate nutrients for optimal growth and yield. A soil analysis is recommended to determine the soil’s nutrient content and pH levels, which will help determine the type and amount of fertilizers required.
It is also important to note that macadamia trees are sensitive to frost and should not be planted in areas prone to frost. If frost occurs, it can damage the flowers and young nuts, leading to reduced yields. Therefore, it is essential to select a site that is free from frost.
Also Read: Macadamia Farming Challenges And Opportunities
Varieties of Macadamia in Kenya
Macadamia nut farming is one of the lucrative agribusinesses in Kenya. Macadamia trees grow well in various parts of the country, including central, eastern, and western regions. There are four approved varieties of macadamia in Kenya that farmers can choose from, classified according to their characteristics and the agro ecological zone they are suitable for.
| Variety | Characteristics | Agro Ecological Zone |
|---|---|---|
| MRG—20 | Pure Macadamia integrifolia variety | Marginal coffee zones of altitudes between 1500—1600 metres |
| Kakuhia | Hybrid of Macadamia integrifolia and Macadamia tetraphylla | High altitude areas of 1500-1800 metres |
| Murang’a 20 | Hybrid of Macadamia integrifolia and Macadamia tetraphylla | High altitude areas of 1500-1800 metres |
| Makuyu | Hybrid of Macadamia integrifolia and Macadamia tetraphylla | Low altitude areas of 800-1200 metres |
The MRG—20 variety is suitable for the marginal coffee zones of altitudes between 1500—1600 metres. Kakuhia, Murang’a 20, and Makuyu are hybrids of Macadamia integrifolia and Macadamia tetraphylla. They are adapted to high altitude areas of 1500-1800 metres and low altitude areas of 800-1200 metres, respectively. Farmers should choose the variety that is best suited for their agro ecological zone to ensure maximum yield.
It is essential to note that grafted varieties take 3-4 years after planting to start producing while local varieties usually take 6-7 years. Farmers should also consult with agricultural experts to get the best advice on the best variety to plant and how to take care of the trees to ensure maximum yield.
Propagation
Macadamia nut is easily propagated using seed but the progeny takes 8-12 years to start bearing nuts and tend to produce low yields. Moreover, the nut quality is unpredictable because the crop is highly heterozygous. Grafting is necessary in order to obtain true-to-type clones and hasten reproductive maturity.
Grafted varieties take 3-4 years after planting to start producing while local varieties usually take 6-7 years. The white mark on the seed should be facing down when you plant it; germination will take between one and three months. After a year, the root-stocks are grafted using the cleft method, with smooth shelled kinds serving as both the scion and the root-stock.
It is important to note that the success of macadamia propagation depends on several factors such as the quality of the scion and rootstock, the timing of grafting, and proper care of the grafted seedlings. It is recommended to propagate macadamia during the rainy season to ensure adequate moisture for the young plants. Additionally, proper nutrition and pest control are essential to ensure healthy growth and high yields.
Land Preparation
Before planting macadamia trees, it is essential to prepare the land properly. Proper land preparation ensures that the soil is fertile and has the necessary nutrients to support the growth of the trees. Here are some steps to follow:
- Clear the land: The first step is to clear the land of any vegetation, rocks, or debris. This can be done manually or with the help of machinery.
- Soil testing: It is important to test the soil to determine its pH level and nutrient content. This will help you determine the type and amount of fertilizer to use.
- Plowing: Once the soil has been cleared and tested, it should be plowed to a depth of at least 30 cm. This will help to loosen the soil and improve drainage.
- Adding organic matter: Organic matter such as compost or manure should be added to the soil to improve its fertility. The amount of organic matter to be added will depend on the soil test results.
- Leveling: After adding organic matter, the land should be leveled to ensure that the soil is evenly distributed. This will help to prevent waterlogging and improve drainage.
- Mulching: Finally, the land should be mulched with organic matter such as leaves or grass. Mulching helps to prevent soil erosion, retain moisture, and suppress weed growth.
By following these steps, you can ensure that your land is properly prepared for planting macadamia trees. Proper land preparation is essential for the success of your macadamia plantation.
Planting
Planting macadamia nut trees in Kenya requires careful consideration of several factors. Here are some key points to keep in mind:
- The trees should be planted at a spacing of 7.5m by 7.5m.
- Altitude is an important factor to consider. Macadamia grows well at altitudes between 1,500-1,850 m. Macadamia tetraphylla and Macadamia hybrids are adapted to high altitudes and are more tolerant to cold than M. integrifolia.
- The tree can reach a height of up to 20m, so it is important to plant them in an area with enough space to accommodate their growth.
- Grafted varieties take 3-4 years after planting to start producing while local varieties usually take 6-7 years.
- It is important to plant macadamia nuts during the rainy season. This will help to ensure that the trees have enough water to grow and establish themselves.
When planting macadamia nut trees, it is important to ensure that the soil is well-drained and has a pH of between 5.5 and 6.5. The soil should also be rich in organic matter and nutrients. Before planting, it is recommended to prepare the soil by digging a hole that is at least twice the size of the root ball. The hole should be filled with a mixture of soil and compost, and the tree should be planted at the same depth as it was in the container.
After planting, it is important to water the trees regularly for the first few months. This will help to ensure that they establish themselves and begin to grow. Once the trees are established, they will require less water, but it is still important to ensure that they receive enough water to produce a good crop.
In addition to watering, it is also important to fertilize the trees regularly. A balanced fertilizer with an NPK ratio of 8-10-5 is recommended. Fertilizer should be applied in three split doses, with the first application made in the first month after planting, the second application made three months later, and the third application made six months after planting.
Overall, planting macadamia nut trees in Kenya requires careful planning and attention to detail. By following the guidelines outlined above, farmers can ensure that their trees grow and produce a good crop.
Fertilizer and Nutrient Management
Macadamia trees require proper fertilization and nutrient management to ensure optimal growth and yield. The following are some guidelines for fertilizer and nutrient management:
- It is important to conduct soil tests to determine the nutrient deficiencies in the soil. This will help you apply the right type and amount of fertilizer.
- Macadamia trees require a balanced fertilizer with a ratio of 8:10:5 (N:P:K). Apply the fertilizer in split doses during the growing season.
- Use organic fertilizers such as compost, manure, and bone meal to supplement the chemical fertilizers. Organic fertilizers improve soil health and fertility.
- Apply micronutrients such as zinc, manganese, and boron as needed. These micronutrients are essential for proper tree growth and development.
- Monitor the soil pH regularly and adjust it if necessary. The optimum soil pH for macadamia trees is between 5.5 and 6.5.
- Avoid over-fertilization as it can lead to nutrient imbalances, which can affect tree growth and yield. Follow the recommended fertilizer rates and schedules.
Proper nutrient management is crucial for macadamia tree health and productivity. By following these guidelines, you can ensure that your trees receive the right nutrients at the right time.
Irrigation
Macadamia trees require consistent and adequate water supply throughout their growth stages. Irrigation is crucial, especially during the first two years of seedling development. A 60cm diameter basin is made around the tree to improve water holding capacity. At this young stage, 20L of water is required every two weeks. Frequency of irrigation is reduced once the tree matures.
It is important to note that overwatering can lead to root rot, and underwatering can result in poor growth and reduced yields. Therefore, it is essential to monitor soil moisture and adjust irrigation accordingly. A soil moisture meter can be used to determine the moisture level of the soil.
In areas with low rainfall, irrigation is necessary to ensure optimal growth and yield. Drip irrigation is the most efficient method of irrigation for macadamia trees, as it delivers water directly to the root zone, reducing water loss through evaporation and run-off.
It is recommended to irrigate early in the morning or late in the evening to minimize water loss through evaporation. Mulching can also help to retain soil moisture by reducing water loss through evaporation and suppressing weed growth.
Overall, providing consistent and adequate water supply through irrigation is essential for the successful cultivation of macadamia trees in Kenya.
Pest and Disease Management
Macadamia farming is susceptible to various pests and diseases that can significantly impact the crop’s yield and quality. Therefore, it is essential to implement effective pest and disease management strategies to prevent or mitigate these problems. Here are some of the common pests and diseases in macadamia farming and how to manage them:
Pests
Nut borer: This pest is a major problem in macadamia farming as it can cause severe damage to the nuts by tunneling into them. To manage nut borers, use pheromone traps and insecticides. Also, ensure proper sanitation practices to eliminate any breeding sites.
Thrips: Thrips can cause damage to the nuts and leaves, leading to reduced yields. To manage thrips, use insecticides and ensure proper orchard hygiene practices.
Stink bugs: Stink bugs can cause damage to the nuts and lead to fungal infections. To manage stink bugs, use insecticides and monitor the orchard regularly to detect and eliminate any breeding sites.
Diseases
Phytophthora root rot: This disease is caused by a soil-borne fungus and can cause severe damage to the roots, leading to stunted growth and reduced yields. To manage phytophthora root rot, ensure proper drainage and avoid overwatering. Also, use fungicides and resistant rootstocks.
Macadamia felted coccid: This disease is caused by an insect and can cause damage to the leaves and nuts, leading to reduced yields. To manage macadamia felted coccid, use insecticides and ensure proper orchard hygiene practices.
Macadamia mosaic virus: This disease is caused by a virus and can cause stunted growth and reduced yields. To manage macadamia mosaic virus, use virus-free planting materials and ensure proper orchard hygiene practices.
Implementing effective pest and disease management strategies is crucial for the success of macadamia farming in Kenya. Regular monitoring and early detection of pests and diseases can help prevent or mitigate any damage, leading to higher yields and better quality nuts.
Harvesting and Post-Harvest Management
Harvesting macadamia nuts is a crucial step in the farming process. It is essential to ensure that the nuts are harvested at the right time to avoid losses. The ideal time to harvest macadamia nuts is when they fall from the trees naturally. This is usually between April and September in Kenya.
It is important to gather the nuts as soon as possible after they fall to prevent spoilage. Farmers should also ensure that the nuts do not get damaged during the harvesting process. One way to prevent damage is to use padded containers or bags to collect the nuts.
After harvesting, the nuts need to be dried to reduce their moisture content. This can be done by spreading the nuts out in a single layer in a well-ventilated area. The drying process can take up to two weeks, depending on the weather conditions.
Post-harvest management is crucial for the quality and shelf life of the macadamia nuts. The nuts should be stored in a cool, dry place to prevent mold growth and insect infestation. It is also advisable to store the nuts in airtight containers to maintain their freshness.
Sorting and grading are other important post-harvest activities. Sorting involves removing any damaged or discolored nuts, while grading involves sorting the nuts by size. This process ensures that the nuts are of high quality and meet the market standards.
In conclusion, harvesting and post-harvest management are critical steps in macadamia nut farming. Proper harvesting and post-harvest practices can help farmers maximize their yields and profits.
Sources: Zuza, Emmanuel Junior, et al. “Review of Macadamia Production in Malawi: Focusing on What, Where, How Much Is Produced and Major Constraints.” Agriculture 11.2 (2021): 152. Link: https://www.mdpi.com/997006
Shabalala, Mlungisi, Michele Toucher, and Alistair Clulow. “The Macadamia bloom–What are the hydrological implications?.” Scientia Horticulturae 292 (2022): 110628. Link: https://www.sciencedirect.com/science/article/pii/S0304423821007354
