Operation of Fertigation Systems System design and uniforrn emitter output and position are the keys to proper design of fertigation systems. The amount of fertilizer applied is directly related to the amount of water applied, fertilizer analysis, and fertilizer injection rate. Small variations in sprinkler or emitter output will greatly affect amount of fertilizer applied per tree, particularly on a seasonal basis. Emitters should be positioned for optimal distribution of nutrients to the limited root zone of young trees. Ongoing maintenance, including the use of screen or media filters, can prevent problems associated with clogging of emitters and damage to tubing.
Considerable controversy exists over proper fertigation rates and frequencies.
Rates usually correspond to those used for granular application but frequency of application may range from weekly to bimonthly to monthly. Current research suggests that tree growth is similar whether materials are applied at weekly or monthly intervals provided that rates of irrigation and fertilization are equivalent. However, frequent applications guarantee that nutrients are being supplied to the tree and ensure against losses from excessive rainfall or irrigation. Since most growers will fertigate when they irrigate, there is no disadvantage to making frequent applications from an energy or cost basis. Fertigation has many advantages over other fertilization systems.