Intercropping is an agricultural practice in which two or more crops are grown together in the same field. This practice is ancient, as numerous records from human societies all over the world indicate. Intercropping persisted in agrarian societies after being rejected by the Western world with the advent of highly mechanized farming. In the late 20th century, Western farmers began to recognize the value of intercropping, and the practice experienced a resurgence in some areas, especially regions where farmers practiced sustainable farming.
There are a number of ways for people to use intercropping. In one form, crops are planted in alternating rows or strips, with the crops being kept separate, but still interacting as a result of proximity. In another, an intercrop or intercrops are planted between the rows after a main crop has started to mature. Intercrops which grow quickly can also be grown in several cycles while a primary crop matures. Intercropping can also be done with crops which are totally intermixed, rather than being separated.
One of the most famous examples of this practice comes from the Americas, where native peoples grew corn, beans, and squash together. This example of intercropping also illustrates many of the advantages of this practice. One advantage is that it increases yields; more can be grown on a single plot with intercropping. It also takes advantage of interdependent relationships between plants, with the intercrops providing cover, shade, nutrients, a trellis to grow on, and other benefits. Some crops may even have insecticidal effects which keep pests from more vulnerable crops.
A wide variety of crops can be mixed with intercropping. Similar cultivars may be grown together, or radically different plants may be grown together, as seen in some wine producing areas where mustard is grown between the vines. This growing technique can be used to condition the soil, by growing nitrogen fixers such as beans, to keep weeds down, as seen when fast-growing crops like radishes are planted among slow-growing grains, and to confer numerous other benefits.
Intercropping is encouraged in the sustainable farming community, with Western farmers adopting a technique which farmers in regions like Asia and Africa have never stopped using. Home gardeners can also utilize this practice to increase yields and promote healthy crops. The benefits of companion planting are not restricted to edible crops, either. Intercropping can be done with flowers, as well, with many flower species such as marigolds having insect repelling properties which can make them useful for natural pest control.