Assisting Vegetable Growers in Florida with Soil Health Evaluation Associated with Cover Cropping/Green Manure Practice During Summer

View the project final report

Commodities

Practices

• Crop Production: cover crops
• Soil Management: green manures, soil quality/health

Cover crops are proving to be vital in the development of soil health. Growing cover crops is perhaps the most valuable strategy we can adopt to feed our soil, build up its fertility, and improve its structure with each passing season. Green manure is a cover crop used primarily as a soil amendment and a nutrient source for subsequent crops. In most production environments, lack of nitrogen limits plant growth more than any other nutrient. Legumes, however, possess a symbiotic relationship with rhizobial bacteria capable of transforming atmospheric N2 into plant usable form and may accumulate large amounts of N via this pathway. Legumes utilized as green manure therefore represent a potentially renewable source of on-farm, biologically fixed N. Unlike chemical N fertilizers, legumes may also fix and add large amounts of carbon to a cropping system. Green manure approaches may also drive long-term increases of soil organic matter and microbial biomass, further improving nutrient retention and N-uptake efficiency. When used in place of fallow, well-chosen green manures may reduce erosion and suppress weeds and specific crop pests. Green manures may also offer habitat or resources for beneficial organisms. All of these processes are quintessential for improving soil quality.

We propose evaluating sunn hemp (Crotalaria juncea) and cowpeas (Vigna unguiculata) as two green manure options that would perform well in Florida during summer.

The research approach comprises of the following four tasks:

• Identification and commitment from cooperative growers;
• Study design;
• Soil testing and analyses;
• Assisting growers adopt cover cropping practice