Use this handy instant greenhouse to stretch your growing season. The Row Shelter Accelerator acts like a cold frame right over the row to increase soil temperature and trap warmth from the sun, causing seedlings to grow up to 25% faster than those in an unprotected row. Plant earlier in the spring, and harvest later in the fall and winter with this very portable crop protection. Constructed by polyethylene greenhouse fabric and mesh. Measures 114 x 56 x 43cm installed (45" x 22" x 17"), - ships flat.