Mature citrus under flood irrigation. Soil permeability affects the length and width of irrigation runs, as well as the necessary grade to assure even distribution of water across the orchard. Assistance in land leveling and design and installation of irrigation systems may be obtained from the Soil Conservation Service. Water delivery to the head of each irrigation pan can be accomplished by an open ditch or an underground pipeline with turn-out valves. Generally, the open-ditch system is used in conjunction with temporary borders and mechanical weed control, where the ditch and borders are put up for each irrigation and removed for subsequent weed control operations.
Water is turn into the tree rows through cuts in the ditch bank.
Operation of this system requires more attention to assure good water distribution in all tree rows, and corresponding operation and maintenance costs are quite high. The permanent valve-pipeline system is almost used with permanent borders and chemical weed control. Operation requires minimal labor and maintenance costs are comparatively low, although initial installation costs may be high. Strip flooding is a modification of conventional irrigation used primarily to conserve water by limiting water flow to half or less of the orchard floor by the use of strip borders along each side of each tree row. Strip irrigation is practiced mainly during orchard establishment to deliver water quickly to young trees without having to irrigate the entire orchard floor.