Compost Quality Guidelines for Organic Vegetable Production

The success of long-term Florida organic vegetable production and maintenance of environmental quality will dependent on soil health and quality. Compost is, primarily, a soil amending product that may improve soil quality and enhance nutrient use efficiency, thus improving the productivity of organic vegetable crops. When considering the use of compost, it is valuable to ask what is the main purpose of the compost application? Compost can be applied as soil conditioner which will increase soil organic matter, improve structure, stimulate biological activity, reduce bulk density, improve water use efficiency, etc. Compost can be applied as nutrient source and although the contribution of nutrients such as phosphorous (P), potassium (K) and micronutrients may be low, it needs to be calculated. Even when compost is not relied on as a nutrient source, its nutrient contribution should be calculated and accounted in the fertility program. Guidelines for the use of compost are still limited or non-comprehensive in addressing all the potential positive and negative effects of compost application in organic vegetable production. Therefore, objective of this presentation will be to present guidelines for the assessment of compost quality, considering physical, chemical and biological properties in order to promote the positive effects of compost on the soil-crop system and minimize any potential negative impact on organic vegetable production.