Florida vegetable farmers who grow cover crops as a green manure between their cash crops anecdotally tout the health benefits, but a two-year study by University of Florida has provided the research to back it up.
In a Southern Sustainable Agriculture Research and Education (SSARE) On-Farm Research Grant, University of Florida soil health expert Jehangir (Jango) Bhadha shadowed the cover crop practices of eight farmers across the state to measure the benefits of using cover crops (mainly cow pea and sunn hemp) as a soil amendment and nutrient source for subsequent cash crops.
In the project, researchers collected soil samples before and after the farmers’ cover cropping program and evaluated the change in soil health properties as a function of cover cropping looking at a host of soil health indicators, including physical, chemical and biological.
Results showed that cover crops provide a myriad of soil health benefits, such as:
- Increasing soil organic matter;
- Increasing water holding capacity;
- Decreasing soil pH, thereby improving nutrient efficiency and microbial activity;
- Increasing soil protein content, thereby storing more nitrogen and making it available to plants through mineralization.
- In some cases increasing phosphorus, one of the most important nutrients for plants next to nitrogen.
“There was a lot of enthusiasm from the growers to learn how their soils behaved when they practiced cover cropping during the fallow period,” said Bhadha, an assistant professor of soil, water and nutrient management at the Everglades Research and Education Center. “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.”