Intercropping

When two or more crops are grown simultaneously in the same field, this is called intercropping or mixed cropping.

Crops are often grown in monoculture. This has several advantages for the easier management of the crop (planting, weeding and harvesting), but it has also some disadvantages.

Many pests and diseases multiply more rapidly in a monoculture than in a mixed crop. In a monoculture, insects can disperse easier and faster. When other crops are present in the field the insects need more time to search for their host plants. Outbreaks of pests and diseases are generally less serious in mixed cropping systems.

Another advantage of intercropping is that the soil is used more efficiently. A mixture of various crops will often give a better coverage of the soil leaving less space for the development of weeds.

Intercropping young tea with cabbage and other vegetables. This is a way to make efficient use of the soil.

If legumes are used in intercropping, they will contribute to improved soil fertility.

Some crops produce odors that repel insect pests of other crops. Examples of crops with repelling odors are onion, garlic and lemon grass. When crops are intercropped with these strong smelling crops they will help to suppress insect attack.

Examples:

	Cabbage-Tomato intercropping is reported to reduce infestation of Diamond-back moth in the cabbage.
	Cabbage-Garlic intercropping will also reduce infestation of Diamond back moth.

In these two examples, the tomato and garlic act as a repellent for the pest.

Intercropping vegetables with marigolds is an effective way to manage root-knot nematodes (Meloidogyne spp.). Most cultivars of African marigold (Tagetes erecta) and French marigold (Tagetes patula) are effective in reducing root-knot population.

Intercropping vegetables with marigolds will suppress populations of nematodes in the soil.
Marigolds as an intercrop suppress populations of root-knot nematodes.