One of the most important aspects of plant health care on Arizona landscapes is the management of irrigation water. Plants have very exacting water needs and meeting those needs appropriately will make them healthier and save you money. When excess irrigation is applied, plants become more susceptible to root rot diseases and water costs go up unnecessarily. When plants receive too little irrigation, they are stressed and become susceptible to secondary pathogens and potential death.
Finding the right balance for your landscape can be challenging, as there are so many variables. For example, irrigation needs often increase as trees and shrubs mature. Species also plays a role. Many imported plant species require relatively high amounts of water while most native plants have adapted to survive with very little. Landscapes that have a combination of native and imported plant species require a more complicated irrigation system to provide the appropriate amount of water to each plant.
Additionally, irrigation needs of landscape plants change with the seasons. When rainfall occurs, irrigation can be reduced or temporarily eliminated. During dry periods, which can be the majority of the year, irrigation requirements increase. This is especially true during the high temperatures typical of the Arizona summer.
For optimal success, have your irrigation system analyzed each year - spring is a good time. Ensure the controller, valves, and emitters are working properly, and replace or repair as needed. Verify that the system is providing the desired coverage and modify it to accommodate growth of plants and changes in the landscape.
On a more regular basis, inspect the system monthly for leaks and for areas that may be receiving excessive or insufficient water. Adjust the controller to ensure sufficient coverage, and repair as needed.