Irrigation Study Shows Cyclical Irrigation Reduces Water Loss and Nitrogen Leaching in Container-grown Trees Glenn Fain, Ken Tilt, and Jeff Sibley P roduction of nursery crops has changed dramatically in the last 40 years, and pressures are mounting to more efficiently use water and nutrients in nursery settings. Growers continue to evaluate various moisture holding components to blend with pinebark, the primary soilless media used by southeastern growers. In the media portion of this study, pinebark was amended with coconut coir or peat to determine if one of these blends would reduce potential container run-off from entering groundwater. Nursery irrigation is still in the early stages of development.
Automatic systems are now in use in many nurseries.
Auburn research recently refined automation to show that cyclic micro-irrigation is a more efficient alternative to the standard practice of overhead irrigation. Micro-irrigation applies water through individual tubes to each container. With cyclic irrigation, a plant's daily water needs are subdivided into more than one application with a small volume applied at specified intervals. Conventional irrigation practices apply the daily water volume in a single application resulting in high run-off through the porous medium. Initial height and trunk diameter were taken after trees were planted, and final growth measurements were taken at the end of the study on September 23, 1997.