Intercropping broccoli and vetch for Integrated Pest Management (IPM) - IntercropVALUES Practice Abstract

Summary

The vetch attracts natural enemies, covers the soil, reducing erosion, enhances biological activity through roots diversity and density; extra organic matter retains soil humidity.
Practical recommendations
-If pest pressure is high, sow vetch before planting broccoli. If it is low, sow once the main crop has already established to reduce potential competition.
-Adapt seeding density for a soil cover that hosts natural enemies of main crop pests. If too high, it can compete for resources with the main crop. If too low, it can fail to increase soil cover or carry insect interactions. Higher vetch development results in an increase of insect diversity at the intercrop.
-With a mechanical seed drill, sow before planting the broccoli. If there is sprinkler irrigation, all the lines of the seed drill can be used. In case of drip irrigation, block the lines that match up with the non-irrigated area and sow at max. 20 kg/ha.
-With a centrifugal fertiliser spreader, sow when the broccoli is already established and before the last cultivation between lines (usually one month after plantation). Seeding density can be 20-30 kg/ha and then buried by a shallow labour.
This technique adds the seed and sowing cost. As broccoli is harvested by hand, the vetch does not affect harvesting.