Virginia Cooperative Extension ServiceAdler, Barry, 1952-McDaniel, Alan, 1948-Relf, Diane2017-11-302017-11-301981-01http://hdl.handle.net/10919/80874Describes the uses of cold frames, sun boxes, and hot beds as a method for extending the growing season and increasing crop yield.2 pagesapplication/pdfen-USVirginia Cooperative Extension materials are available for public use, re-print, or citation without further permission, provided the use includes credit to the author and to Virginia Cooperative Extension, Virginia Tech, and Virginia State University.LD5655.A761Extension publicationprotected cultivationfood cropsCrop yield