Contents of this publication do not necessarily reflect the views and policies of the Office of Water Research and Technology, U.S. Department of Interior, nor does mention of trade names or commercial products constitute their endorsement or recommendation for use by the U.S. Government. The fequency may range from several irrigations per week to daily irrigation to even several irrigations per day in greenhouse and nursery settings. Another widespread use of high frequency irrigation is found in the various low pressure systems such as drip, trickle, bi-well, and bubbler. These systems deliver relatively small amounts of water to the root zone as a consequence of factors such as limited water, shallow soils, limited water holding capacity, and high erosion potential. The yield expected under high frequency irrigation may not be signsficantly increased over well-managed conventional irrigation, but increased efficiency of water, energy, fertilizer, and labor make even modest yield increases important.
Nutrient management is critical with high frequency irrigation.
Nitrogen in particular is susceptible to loss from the root zone by leaching, so high frequency irrigation systems require frequent, light nitrogen applications. This is facilitated by distribution of nutrients through the irrigation system. Other chemicals such as soil fumigents for nematode control, systemic insecticides, and herbicides can also be injected into the irrigation system and applied very uniformly to the crop. This research was directed toward defining the best management practices for irrigation timing and fertilizer applications under high frequency irrigation.