Intercropping

Intercropping is growing two or more crops next to each other at the same time. The main purpose of intercropping is to produce more crops in a given area. It also makes use of resources (nutrients) that would otherwise not be used by a single crop. Crops are selected such that their nutrient requirements are different. This way, the crops can give the same returns but require less space.
Things to consider when choosing which crops to mix include the soil, climate and varieties. It is very important not to have crops competing with each other for space, nutrients, water, or sunlight. An example of an intercropping strategy is planting one crop that has deep roots with another that has shallow roots.
Intercropping has been proposed as an alternative to slash-and-burn farming, which is very bad for the environment.
Conserving soil
Intercropping also helps to conserve soil. When One crop is harvested and it starts raining the second crop grown in that farm will not let to erode the soil easily by water. Hence the soil is conserved. 
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Conserving soil
Intercropping also helps to conserve soil. When One crop is harvested and it starts raining the second crop grown in that farm will not let to erode the soil easily by water. Hence the soil is conserved.