Fall Watering information for Arizona Gardening
Fall is here, and its a great time to replace lost plants or install a new landscape. Soils are still warm, which encourages root establishment, but water needs are not as demanding, allowing for greater success. In fact, water needs for plants are about half as much as they were in June. Recommendations below are for plants that are established in the landscape (in the ground about 2 years).
Summer grass (Bermuda) - once every 6 days Overseeded cool season grass (rye) 4x per day for first 7-10 days to germinate, then once every 3 days
If trees and shrubs are on the same valve:
Desert Adapted - once every 21 days High Water Use - once every 10 days
Desert Adapted - once every 24 days High Water Use - once every 12 days
Desert Adapted - once every 18 days High Water Use - once every 9 days
Groundcover and vine watering:
Desert Adapted - once every 18 days High Water Use - once every 8 days
Cacti and succulent watering - once every 28 days Annuals watering - once every 4-5 days Wildflower watering once every 1-2 days to germinate, then once every 3-5 days
Bonus tip: New plantings need more frequent watering. After planting, water every 3-4 days weeks 1 & 2, every 6-7 days weeks 3 & 4, every 7-10 days weeks 5 & 6, and then gradually extend time between irrigations until plants are established.
Note: These recommendations are a general guideline only and may need to be modified for your specific site conditions.
Tips provided by the City of Mesa Utilities Department. Check their website CityofMesa.org to find the link if you would like to receive them via email. (sorry- can't post a link here)
Another important thing to consider once you know when to water is how long to water. Trees need to be watered long enough so that the water penetrates at least 3 feet. Shrubs 2 feet. Groundcover 1-2 feet. Using a drip system and the correct amount of emitters, each foot would require about an hour of watering. For example, to water a tree to a depth of three feet would require approximately 3 hours of drip watering. As it has been said repeatedly before in this forum: Better to water infrequently and deep than frequently and shallow. Also make sure that you are watering trees near the radius of the branches and not near the trunk. For example, if your tree has branches that extend 6 feet from the trunk your emitters should be placed at least 4 feet from the base of the trunk.
Thanks to AZTREELVR and Desert_Owl for their expert advice!