Companion plants
Companion plants are service plants sown during a main crop, in the plot.
They are intended to provide one or more benefits (ecosystem services) to the current crop or to those following in the rotation and do not, however, have a productive purpose (corresponding to a minimization of provisioning services).
Description
This association can notably help in pest control and weed management. For example, increasing the density and uniformity of soil cover reduces weed emergence. Some plants can also serve as a support for a second.[1]
One management option is the destruction of the companion plant before harvest, when it was sown before or at the same time as the cash crop. This is, for example, the case in the intercropped rapeseed technique. The other option is to leave the companion plant as a cover during the intercrop period after having established it at the end of the previous crop cycle.
If the associated cover consists of a perennial crop overlapping the cycle of several main crops, it is then called a permanent cover. The use of alfalfa is often cited in this context. The benefits of the service plant are increased here with the duration of the cover presence, which is most often between 18 and 36 months. However, the management of permanent covers is delicate. The success of this technique depends on the regulation of the cover so that it does not dominate the cash crop.
Services provided
Weed regulation
Disease regulation
Pest regulation
