1.3.2.c Choice of cover crop(s)

The choice of cover crop(s) is an important aspect of planting because it depends on the winegrower's objectives. That said, the decision should be made based on the intrinsic characteristics of the plots and the climate. Certain species and varieties are less resistant than others during harsh winter conditions. When choosing, the following criteria should be taken into account:

• Soil type: Most varieties are adaptable to all soil types but many have preferences or are particularly suited to one soil type more than others (hydromorphic, acid, heavy soil...). The seedlings will often have specific needs when they come out of dormancy.

• Soil objectives: Effects on soil structure, nitrogen, weeds... Several options are possible and it is often best to consider a mixed selection. It is worth checking to see the possible types of inter-family pairings (a cereal, a cruciferous plant...). A cereal/legume duo works well, as is the case for oats and alfalfa for example.

Three main families are used: grasses, legumes and crucifers. They can be sown separately or at the same time to benefit from their complementary properties.

The best solution would be to sow a mixture of species with complementary properties. This would help meet several soil obectives: restructuring the soil, adding nitrogen, repelling weeds and even nematodes. In addition to these advantages, mixing varieties also helps to promote biodiversity and create ecological niches: certain crop families are also used to diversify the species in a mixture and to promote bee pollination. Indeed, many melliferous plants are present in small percentages in certain mixtures.
The right conditions must be put in place for sowing to ensure successful and homogenous shoot growth. For example, it may be necessary to lightly plough the soil first and also drain it to limit the risk of crust formation on the topsoil.