The main goal of intercropping is to achieve the highest yield on a particular land by maximising the potential of the resources present.
The problem is that when two or more crops are planted together, they compete for light, water and nutrients, and could therefore negatively affect each other. Successful intercropping depends on maintaining a balance between competition and facilitation.
Growing two crops together is especially beneficial when the plants interact to increase the fitness and yield of one or both crops.
For example, lodging-prone plants, which can easily tip over in wind or heavy rain, can be given structural support by their companion crop.
Intercropping of compatible plants can also encourage biodiversity by providing a habitat for a variety of insects and soil organisms that would be absent in a single-crop environment. Planting a legume, for example, will improve soil quality through its nitrogen-fixing ability, which provides valuable nutrients.
Alternatively, trap cropping (planting a crop more attractive to pests than the production crop) can help control pests.
In short, it’s important to select crops that are compatible and work well side by side. The most common intercropping system practised in South Africa is probably the grain crop-legume combination, usually maize rows inter-planted with either beans or cowpeas.
Farmers with a livestock component like to intercrop with maize and cowpeas, with the entire maize plant, including the cobs, available for grazing. The economic sum works out very favourably, with no mechanisation or labour costs as the animals ‘harvest’ their own food on the land.
Intercropping can increase yield per hectare but only if the farmer has the knowledge to select suitable crops, and the time and management expertise to care for them.
The key is to do one’s homework and recognise that this intensive farming system requires increased management.
Source: Mathews, J. 2018. ‘The pros & cons of intercropping’. Grain SA.