| Organic greenhouse vegetable production is characterized by very high nutrient demands within short growing periods and high nutrient exports via products sold. Therefore, meeting crop nutrient demands and maintaining long-term sustainability in these systems is highly challenging. To gain insight in current practices this study assessed fertilization strategies and nutrient flows of ten organic horticultural farms (22 greenhouses and polytunnels) in Southwest Germany belonging to the two organic farming associations Bioland and Demeter (biodynamic) for a cropping period of three years. Soil samples were taken to analyze plant available phosphorus, potassium, soil organic carbon, pH and salinity. Crop rotations in the greenhouses were very diverse, though... |
