Improving Soil Health with Cover Crops and Other Soil Amendments in Florida Citrus Groves
Posted August 2025
Researchers: Sarah Strauss, Emma Dawson, Gabriel Pugina, Brittney Monus, Ute Albrecht, Ramdas Kanissery
Contact: Sarah Strauss, UF/IFAS SWFREC strauss@ufl.edu
Summary:
Healthy soils can sustain biological productivity, maintain environmental quality, and promote plant health. One strategy to boost Florida soil health is through increasing soil organic matter (SOM). Planting cover crops (CC) or applying compost or humic acids could enhance SOM and soil health. We are examining the impact of these three methods in commercial Florida citrus groves and at the UF/IFAS Southwest Florida Research and Education Center. All trials include a no-treatment/grower standard control and either CCs in the row middles, or compost or humic acids broadcast around the trunk. Planting mixtures of legume and non-legume CC in Flatwood groves altered the soil microbial composition and nitrogen availability, as well as increasing SOM. Yield and °Brix also significantly increased in one Flatwood grove after three years of CCs. However, CCs in a grove on the Ridge had no significant impact on the trees, soil nutrients or microbes after three years. Applying compost around trees in the Flatwoods significantly changed the soil microbial activity and some nutrients, and changes depended on the rootstock variety. However, humic acids had no significant impact on soil microbes, nutrients, or tree growth. Overall, our results suggest: 1) CC and compost improvements in SOM, nutrient cycling, and microbial composition in citrus row middles can be observed during the first three years of treatment but results depend on location and management of the grove, and 2) humic acids had little impact on trees or soil microbes and nutrients. Increasing SOM and soil health is a long-term process, so trials are still ongoing.
Take Home Message:
- Cover crops can change soil organic matter, soil microbial community, and their functions.
- The magnitude of cover crop changes can depend on the grove location, management, and establishment of cover crops.
- Compost can also alter soil organic matter, microbes, and nutrients, but humic acids had little effect on these properties.
