SOILLESS University of California, Davis（无污点的加州大学戴维斯分校）.pdfVIP

UC Davis, Vegetable Research and Information Center Soilless Culture of Greenhouse Vegetables SOILLESS CULTURE of Greenhouse Vegetables Almost all of the vegetables we find on grocery- the use of spaghnum peat, vermiculite, or bark chips. store shelves are produced either directly or These are the most commonly used materials, but indirectly in open-field soil. However, soil itself isnt others - such as rice hulls, bagasse (sugarcane necessary for plant growth - only some of its refuse), sedge peat, and sawdust - are used constituents. sometimes as constituents in soilless mixes. Straw Field soil serves two basic purposes: it acts as a bales have been used as growing medium in England reservoir to retain nutrients and water, and it and Canada. Rockwool (porous stone fiber) is used provides physical support for the plant through its in Europe, but there is little experience with it in this root system. Artificial means can also provide these country. important requirements for plant growth with equal Since the major constituent of the media in (and sometimes better) growth and yield results artificial growing systems may be solid or liquid, it is compared to field soil, although at substantially appropriate to use the term soilless culture in greater expense. Well-drained, pathogen-free field reference to this general type of growing system and soil of uniform texture is the least-expens