Practices to improve soil fertility and nutrient availability in organic fruit orchards (Biofruitnet Practice Abstract)

Leguminous plants grown as living mulch or cover crops (in mixture with grasses) increase soil fertility and microbial biodiversity or activity, with a positive effect for the overall soil biological fertility through the seasons. Practical recommendation To improve soil fertility and nutrients availability, we recommend to: • Use legumes (e.g., pea) as short-term living mulches in the tree row • Use mixtures of a leguminous and grass (e.g., micro-clover and sheep grass) in the inter-row. The cut can then be used as row mulch • Apply clover grass silage to orchards as a farm internal nutrient source • Sowing winter peas or early sowing of spring peas allows Nitrogen (N) release after incorporation reaching a sufficient N supply during flowering. Notice that N availability from mineralization of the pea biomass depends on the time of sowing and the biomass incorporation into the soil • Leguminous cuts from the inter row can serve as a N source later in the season, as mineralization proceeds slowly • Clover grass silage has higher storability than the inter row grass cuttings. Hence, application of clover grass silage allows to plan earlier applications (e.g., in autumn of the previous year). If availability of land and specific machinery for silage is an obstacle, we recommend setting up collaboration with arable farms