Arid

Before applying lime to increase lower soil pH the following should be considered. Equipment required: soil pH testing kit, protective goggles and mask, agricultural lime, shovels/forks/hoes, and disk harrow, drag harrow or hoe if available.

• Step 1: Use a pH testing strip to determine soil pH levels, making sure to test surface and sub-surface acidity.
• Step 2: Measure area of land to be treated in order to determine amount of lime for purchase. Application should be calculated as metric tonne per hectare, depending on soil pH and crop. Lime requirements will differ depending on soil type and level of acidity in the soil. Application volumes can be guided by suppliers.
• Step 3: Purchase lime according to requirements from agricultural supplier. Savings could be realised if purchasing as a group of farmers.
• Step 4: Apply lime to the soils at least two months prior to planting directly after harvesting to allow the lime to react with the soil, and positively impact the pH.
• Step 5: Mix lime and soil well in order to reduce soil acidity. This is normally achieved through disk tilling but can be done manually using a drag harrow or hoe. However, this can be an intensive process.
• Step 6: Test pH prior to planting to ensure amendments have improved soil pH.
• Step 7: Plant crops. Monitor crop performance, and harvest results with a view to understanding impact of lime treatment.
• Step 8: Following harvest, test soil pH again.

Application of lime can be part of an Integrated Soil Fertility Management (ISFM) practices.

While a practical solution, this soil amendment should be informed by research and discussion with extension officers and lime suppliers. On-farm storage and management of lime should be included in this dialogue.

Organic fertilisers can be produced at the household level or purchased. On-farm production includes stock-piling animal manure, crop residues, and other organic waste, following appropriate guidance for processing and usage.

To apply organic fertilisers the following should be considered:

• Step 1: Assess field area where fertiliser is to be applied, and fertiliser needs – poor crop performance, low organic matter content, etc.
• Step 2: Ensure that fertiliser is available in sufficient quantities for application in all target or priority fields.
• Step 3: Ensure organic fertiliser – especially green manure/crop residues – are broken-down/chopped to aid breakdown/integration with soil.
• Step 4: Monitor soil nutrient levels and crop performance (in the light of prevailing climatic conditions) to determine success of organic fertilisers.

To effectively apply a green manure approach, the following should be considered:

• Step 1: Select legumes that grow well under local conditions and in local soils. Green manure crops should be resilient and require few crop management practices. A thorough investigation should be made to ensure that green manure crops are appropriate for the local conditions in terms of rainfall, climate, soil pH and texture, and salt tolerance.
• Step 2: Identify the appropriate time for planting the green manure crop to ensure growth, but not impacting the primary crop. Especially if the secondary crop is a climber/creeper. Main crop may need to be mature before planting the manure crop, as if a creeper, it may outcompete or constraint growth of maize or sorghum plants.
• Step 3: If seeking to enrich soil properties, the farmer must allow crop residue to remain in the soil longer. This is particularly relevant with multiple uses – e.g. soil amendments and livestock fodder. In these cases, pods can be harvested for fodder, and the remaining plant residue left in the field to cover the soil.
• Step 4: Crop planting should be alley cropped between the primary crop rows, allowing management of the primary and secondary crops, also reducing the competition between the primary and the secondary crop. If the secondary crop also has pest management properties, it may be beneficial to consider boundary planting.
• Step 5: When harvesting the secondary crop, the farmer should consider leaving the residue in the ground. If it is uprooted, it should left on the soil surface. A common mistake is to remove it from the field and accumulate it in one location, missing the benefits of cover-crops, and exposing the residue to decay.

Unless local examples are available, small test plots should be used to test different cover crops to determine which is the most appropriate, and if necessary, demonstrate value to farmers and communities. As the secondary (green manure) crop is not a direct cash-crop, you may need to ensure expectations are measured. It may take several years to develop enough green manure crop to contribute to crop production; hence, crop production has to fit around existing cash/subsistence crops. Furthermore, benefits may not be realised within a single planting season., e.g. Nitrogen may only be available in the soil in the subsequent season.