Compost Use in Vegetable Production
Methyl bromide and other soil fumigants have been heavily relied upon to control soilborne pathogens, nematodes, and weeds in plastic mulched vegetable production in Florida. However, negative aspects of their use on the environment and human exposures have increased the interest in non-chemical alternatives such as the use of composting, solarization, and soil bio-pesticides.
Many of Florida’s vegetable production soils are sandy-textured, low in soil organic matter, nutrients, and water holding capacity, and therefore inherently low in fertility and highly leachable. The addition of organic matter via composts application has been shown to enhance soil physical properties, water holding capacity, and nutrient levels, and ultimately to improve plant growth, yield, and water quality. In 2013, Florida’s counties, cities, and private companies produced 30.8 million tons of solid waste. These solid wastes consist of non-hazardous, organic wastes (biosolids, animal wastes, food wastes, yard trimming wastes, and municipal solid wastes), for which land application appears to be a viable option. Many of these materials can be used with positive responses in the production of vegetables, fruits, and ornamentals plants. Thus, research on compost use and integration into Florida vegetable production systems is of great importance and part of the Vegetable Horticulture Program responsibilities.
- What is Compost?
Composting is a biological decomposition process where microorganisms convert raw organic materials into relatively stable humus-like material. During decomposition, microorganisms assimilate complex organic substances and release inorganic nutrients. An adequate composting process kills pathogens and stabilizes compost organic carbon before the material is land-applied. Currently, the majority of wastes produced in Florida are landfilled or burned. If all biodegradable material in Florida was composted, approximately 8 million tons of compost could be produced annually, to be used on Florida’s crop production.
- Compost Education
- Organic Amendments
Non-chemical alternatives to methyl bromide as a soil fumigant, such as organic amendments, have been shown to be not as effective, but do offer promise of more sustainable solutions. The Vegetable Horticulture Program has worked on studies that aim to evaluate the long-term effects of organic amendments on pepper (Capsicum annuum L.) and watermelon (Citrullus lanatus (Thunb.) var. lanatus) growth, yield, and soil chemical and physical properties. In this research the experiment site has received yearly organic amendment applications since 1993. Results from 10 years of study suggest that regular organic amendment applications to a Florida sandy soil can increase plant growth and produce similar yields with less inorganic nutrients than standard fertilization programs. Grower input costs could be reduced through water and fertilizer conservation, which would also decrease negative environmental effects.