Subirrigation
In agriculture, subirrigation is a method of irrigation used in commercial greenhouse operations. Water is delivered from below, absorbed upwards, and the excess collected for reuse. Subirrigation is usually used with potted plants.
Three basic types of subirrigation system are in general use: ebb-and-flow (bench-mounted enclosures holding pots are filled and then drained); trough (water is flowed through bench-mounted, slightly sloping enclosures containing pots); and flooded floor (special sloped concrete flooring is flooded and drained).
Subirrigation has been growing in popularity since the 1990s. Advantages are water and nutrient conservation, and labor-saving. The outfitting cost is relatively high. Potential problems, such as the possibility of increased presence of disease in recycle water, have only begun to be investigated.