Tuesday, July 31, 2012
Grand Ballroom
Vermicomposting is a process in which worms break down organic material and transform it into vermicompost, a valuable horticultural product. Additionally, research has found that vermicomposting can divert a significant amount of organic waste from the waste stream. The purpose of this study was to implement a pilot project vermicomposting system at Texas State University using red wiggler worms (Eisenia fetida) and cafeteria food waste as a primary feedstock to determine the potential economic value of the system. Approximently 50 pounds of food waste was collected weekly from one cafeteria on campus and combined with shredded university paper waste. Vermicomposting bins and systems were reviewed and a layered bin system was constructed using recycled 5-gallon food service buckets. The system was constructed in an 8’ x 10’ shed to reduce input costs in maintaining temperatures necessary for the worms to thrive. Worms were checked 2-3 times weekly and rotated through the system in approximately 3–4 months. Vermicompost was harvested at the end of each semester and then weighed and packaged for sale using a food scale. Worm castings were also integrated into the university gardens and greenhouse. Economic analysis results demonstrated the value of the operation to the university in terms of the product generated for use for sale as a fertilizer and the diverted cost of waste disposal versus the cost of operation. Results of the economic analysis will be presented and will be valuable in adding to the literature the potential value of vermicompost as a substitute for synthetic fertilizers or as an ingredient in compost-based potting mixes.