Organic herbage legume intercropping

Summary

The project aimed to investigate the management parameters, options and performance of a system of strip intercropping of herbage legumes and organic vegetables in which nitrogen transfer and conservation is effected by a combination of grazing ruminant livestock and crop rotation. The study will involve 3 inter-related approaches: a theoretical evaluation, a field experiment and a financial and economic evaluation. The theoretical evaluation will be achieved via a combination of a review of relevant literature and consultation with horticulturists, scientists and representatives from the organic food industry. The field experiment will be conducted to investigate the management parameters and performance of a theoretically promising intercropping system consisting of red clover/timothy as the legume and spring cabbage as the first crop followed by a second crop such as salad beetroot, with sheep grazing introduced at certain stages. Objectives of the field experiment will include assessing the effects of varying strip width on system performance, examining the effects of sheep grazing on transfer of N from legume to crop and investigating the effects of crop rotation on nutrient transfer and conservation. A financial evaluation of the proposed system will be conducted initially using costs and values derived from literature and industrial sources; this will then be refined using data provided by the field experiment. The economics and implementation of the system will be assessed via a survey of organic vegetable growers and via a market assessment in collaboration with Safeway plc.