What is the proper temperature and length of time needed to sterilize landscape fabric?

J.J.GeorgiaAnswer: As a guideline, to completely eliminate pests, maintain 158°F or higher for 30 minutes, or 140°F or higher for one hour. It might be difficult to get your greenhouse to that temperature without incorporating another form of solarization, such as black plastic bags. Most often just leaving the fabric exposed to sunlight can destroy organisms through UV exposure. Both sides of the fabric need to be exposed to sunlight and need to be clean (i.e. without dirt clods and debris). In a greenhouse the UV rays are partially blocked by either glass or plastic. I would encourage you to spread out the landscape fabric outside in the direct sunlight for several days on each side, to ensure that the entire fabric is exposed to UV. References: Stapleton, C.L. et al. 2008. Soil Solarization for Gardens and Landscapes.University of California IPM Program. http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn74145.html