Water supplied to the soil (from ditches or through underground tile lines, or perforated pipe lines, or by natural subsoil moisture) in sufficient amounts to maintain a water table sufficiently close to the soil surface to supply adequate water quantities for crop needs.
Utilization of subsurface drainage to irrigate crops through the use of capillary rise of water from the full drainage tiles upward through the soil into the rooting zone.
In agriculture, subirrigation, also known as seepage irrigation, is a method of irrigation where water is delivered to the plant root zone from below the soil surface and absorbed upwards. The excess may be collected for reuse.