10 Best Fertilizers for Groundnut Farming in Kenya

Groundnut farming in Kenya is a vital agricultural activity, providing a significant source of income for farmers across the country. However, to maximize yields and ensure healthy soil, using the right fertilizers is essential. Groundnuts (peanuts) require specific nutrients, particularly nitrogen, phosphorus, and potassium, which promote robust plant growth, enhance pod formation, and improve overall yield quality.

Each fertilizer type is tailored to address specific soil deficiencies and enhance productivity.

1. NPK Fertilizers (10-20-10)

NPK fertilizers are among the most commonly used fertilizers for groundnut farming. The 10-20-10 formulation is especially beneficial for groundnuts as it balances nitrogen (N), phosphorus (P), and potassium (K), which are critical for plant growth, root development, and pod formation. Phosphorus, in particular, supports the development of the root system, making it essential during the early growth stages of groundnuts.

Nitrogen enhances leaf and vegetative growth, while potassium plays a role in regulating water balance and disease resistance. Research by the International Food Policy Research Institute (IFPRI) indicates that an application of NPK fertilizers can increase yields by up to 30%. It’s recommended to apply NPK fertilizers in the planting and flowering stages to optimize productivity.

2. Urea Fertilizer

Urea, with a nitrogen content of 46%, is an excellent source of nitrogen, which groundnuts need for vigorous growth. Nitrogen promotes healthy leaf development, supporting the photosynthesis process. According to the Kenya Agricultural and Livestock Research Organization (KALRO), groundnuts benefit from additional nitrogen during the early vegetative stages. However, overuse can lead to excessive vegetative growth at the expense of pod development.

It’s important to apply urea in moderation, especially since groundnuts can fix nitrogen through symbiotic relationships with rhizobia bacteria. A study conducted by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) found that proper nitrogen management using urea could increase yields by 25% to 35%.

3. DAP (Diammonium Phosphate)

DAP is a phosphorus-rich fertilizer that is widely used to promote strong root development and early growth of groundnut plants. Phosphorus is a critical element for groundnuts, particularly during the early stages of germination and root establishment. DAP contains both nitrogen and phosphorus, making it a great option for improving initial plant growth.

A study from the University of Nairobi found that the application of DAP leads to improved crop emergence and stronger plant health, directly contributing to higher yields. For groundnut farmers in Kenya, using DAP at planting time ensures adequate nutrient availability to support early plant development, which is crucial for the formation of a healthy crop.

4. Kieselguhr

Kieselguhr, also known as diatomaceous earth, is a natural source of silicon that improves soil structure and enhances the plant’s resistance to pests and diseases. Groundnut crops benefit from silicon, as it strengthens cell walls and enhances root system efficiency. It also helps improve water retention in sandy soils, a key factor for groundnut farming in regions like Kenya’s arid and semi-arid areas.

According to a report by the International Rice Research Institute (IRRI), crops treated with silicon-based fertilizers tend to show improved resilience to environmental stresses. Kieselguhr, when used in combination with other fertilizers, can boost groundnut yield by improving plant durability and health, reducing the risk of crop failure due to drought or disease.

5. Gypsum

Gypsum, a calcium sulfate mineral, is crucial for improving soil structure and providing calcium to groundnut plants. Calcium enhances the stability of plant cell walls and plays a key role in preventing blossom end rot, a common issue in groundnut farming. Moreover, gypsum helps in ameliorating soil acidity and improving soil porosity, leading to better root development and nutrient absorption.

Groundnut farmers in Kenya, especially those in areas with alkaline soils, find gypsum particularly useful for balancing soil pH and enhancing nutrient availability. According to a study by the International Institute of Tropical Agriculture (IITA), calcium from gypsum improves groundnut pod and seed quality, leading to higher market value.

6. Ammonium Nitrate

Ammonium nitrate is another highly effective nitrogen fertilizer that supports groundnut crops during their growth stages. It provides nitrogen in both ammonium and nitrate forms, which are quickly absorbed by plants. This fast-release nitrogen helps in boosting vegetative growth and improving overall yield potential. Studies show that the use of ammonium nitrate increases groundnut yields by enhancing the overall plant health and reducing nutrient deficiency symptoms.

For Kenyan farmers, applying ammonium nitrate during early vegetative stages is recommended to ensure that plants have sufficient nitrogen during crucial growth periods. However, overapplication can result in excessive growth and lower pod formation, so careful application is advised.

7. Magnesium Sulfate

Magnesium sulfate, also known as Epsom salt, provides magnesium and sulfur, two nutrients essential for groundnut growth. Magnesium is a critical component of chlorophyll, enabling efficient photosynthesis, while sulfur helps in protein synthesis and overall plant metabolism. Groundnuts require magnesium for leaf and pod development, and a deficiency can lead to chlorosis, which reduces plant vigor.

Sulfur also helps in nitrogen fixation by rhizobia bacteria, improving nitrogen use efficiency. Research from KALRO indicates that magnesium sulfate application can lead to higher groundnut yields by improving nutrient uptake and supporting robust plant growth, especially in soils deficient in magnesium and sulfur.

8. Compost and Organic Fertilizers

Using organic fertilizers like compost can significantly enhance soil fertility and improve soil structure. Organic matter enhances microbial activity, which helps break down complex nutrients into forms that plants can easily absorb. Groundnuts benefit from the slow-release nature of organic fertilizers, which ensures a steady supply of essential nutrients throughout the growing season.

Additionally, organic fertilizers improve soil moisture retention, making them particularly beneficial for groundnut farming in Kenya’s dry regions. According to the Food and Agriculture Organization (FAO), organic farming practices that include composting can increase crop resilience and improve soil health over time, leading to better long-term yields.

9. Triple Super Phosphate (TSP)

Triple Super Phosphate (TSP) is a concentrated form of phosphorus fertilizer that boosts root development and flower formation in groundnuts. Phosphorus is essential for energy transfer within the plant and plays a key role in root establishment and early plant growth. A study by KALRO revealed that groundnut crops treated with TSP exhibit higher root growth, which is vital for nutrient uptake and overall plant health.

Applying TSP during planting ensures that groundnuts have an ample supply of phosphorus for early development, thus improving the chances of a successful crop. The high phosphorus content in TSP is especially beneficial for sandy or low-phosphorus soils commonly found in various regions of Kenya.

10. Zinc Sulfate

Zinc is an essential micronutrient that plays a crucial role in the synthesis of enzymes, proteins, and growth hormones in groundnut plants. Zinc deficiency can lead to stunted growth, chlorosis, and poor pod formation. In Kenya, where soil zinc deficiency is common, zinc sulfate is an important fertilizer to consider for groundnut cultivation.

Research from ICRISAT indicates that groundnuts grown in zinc-deficient soils show a significant improvement in yield and pod quality when treated with zinc sulfate. For Kenyan farmers, zinc sulfate should be applied at planting time or during flowering to enhance crop development and ensure high-quality yields.