Cover crops in organically managed agro-ecosystems represent an important tool to manage all at once soil fertility, pests, disease and weeds. Cover crops are usually not so common in specialized vegetable systems but they can be introduced as living mulch, intercropped with cash crops. If this management option is chosen it is important to reduce the competition between the main and cover crop and to use a crop management strategy able to optimize the ecological services within the field and the farm as a whole.

The INTERVEG partners settled parallel experimental field trials in 4 EU countries (Italy, Denmark, Slovenia and Germany) to evaluate the effect of introducing living mulches in organic vegetable production systems. Cover crop sowing period, root pruning as well as spacing or yielding crop and cover crop density are the relevant factors that were under investigation in order to optimize the performance of the living mulched agro-ecosystems in comparison with the sole crop systems. The selected yielding crops had been identified as cauliflower for the 4 countries, artichoke for Italy and leek for the other three countries.

A total of 12 field experiments have been carried out during the project spam: 8 in research farms of the research Institutions involved in the project and 8 in commercial organic farms (on-farm research). A detailed list of common measurement has been set up and, accordingly, results have been collected in each location.

The data collected include yield and marketable yield, number of plants, N, P, K content, soil, water, competition indices for weeds, cover and cash crops. In addition data on pest and beneficial insects, energy consumption and costs have been also collected in the different European areas. Since also commercial organic farms are involved in the project as pilot farms, the effect of living mulch at larger scale, such as impact on pest and beneficial insects has been evaluated. On-farm research activities were also aimed to encourage farmers involvement and to support dissemination activities.