CloseFerVeg

Demand for organic vegetables is increasing. We need to eat more plant-based foods and more vegetables for the sake of the climate, environment, and health. However, vegetables pose a high risk of nitrogen loss after harvest, and intensive production degrades soil quality and fertility. Previous research projects have shown that soil carbon content decreases by about 20% in a so-called 'sustainably intensified' crop rotation trial over 5 years due to intensive vegetable rotation and issues with timely establishment of cover crops. 

Cover crops are otherwise known as a strong tool to reduce nitrogen loss and build soil fertility. Other research results and practical experience have shown that undersowing overwintering cover crops into the main crop can be the answer to challenges with nitrogen loss and soil degradation in organic vegetable production on clay soil. However, there is a lack of knowledge about species selection and management methods for cover crops to ensure the crop's resource requirements, so high yields are ensured, especially on sandy soil. At the same time, there is a lack of knowledge about reducing climate and environmental impact using cover crops.

Project Purpose

CloseFerVeg aims to:

• Reduce nitrate and nitrous oxide loss from intensive vegetable production, which is known for the risk of large nitrogen losses after harvest.
• Maintain soil fertility and carbon sequestration in vegetable production with high yields. 
• Document the effects on the climate footprint of vegetables and the significance of undersown cover crops in research and demonstration trials in the field - using life cycle assessment (LCA).
• Spread knowledge about climate- and environmentally-friendly production of organic vegetables using cover crops. 

Research and demonstration to achieve the goals will be done by increasing knowledge and developing tools for:

• Undersowing overwintering cover crops in vegetables with a high risk of nitrogen loss in relation to cover crop species and cultivation (timely establishment, complementarity for intercropped species) to achieve good plant development for both the crop and cover crop with balanced competition for resources above and below ground to achieve agroecological effects.
• Documentation and reduction of climate and environmental impact via LCA (including carbon storage in the soil) for vegetables and undersown cover crops.

CloseFerVeg is carried out interdisciplinarily and with the Living Lab method between Denmark's largest vegetable consultancy firm, two university partners, and two vegetable producers, and will give organic vegetables a significant boost in climate friendliness.