When in Drought….

Arizona’s water supply outlook is sobering as climate conditions are trending hotter and drier.  Arizona’s population is rising, increasing demand. As more pressure is put on the water supply, water expenses will increase and the pressure to conserve water grows by the day.

What are the concerns about the Arizona water supply and landscape water use?

• The Tier 1 Water Shortage on the Colorado River is in effect for 2022, though it is not affecting municipal water deliveries.
• Future water shortages loom and point to a decrease in available water for municipalities, which will likely affect the availability and cost of water for landscapes.
• Some plant species are already struggling under these harsher climate conditions.
• Improper watering practices are making trees and plants more susceptible to drought stress and future water shortages.
• Irrigation system efficiency and plant resiliency need to be the focus now.

What can be done to prepare for less water and harsher climate conditions?

• Choose native or desert adapted plants.
• Limit turf areas to save water; consider turf conversion for low use and marginal areas.
• Conduct regular inspections of irrigation systems.
• Make necessary irrigation repairs and efficiency upgrades.
• Water the entire plant root depth at each watering event to promote optimal root growth and resilience to temperature extremes and drought.
• Proper emitter/sprinkler placement is extremely important:
  • As trees grow, emitters need to be added to irrigate the active root zone around the dripline, and capped closer to the tree trunk.
  • It is cheaper and easier to add and cap emitters than to remove and replace a dead tree.
• Avoid frequent, shallow watering:
  • It promotes weak, shallow roots that are more susceptible to temperature swings and drought (exception: sandy soils need to be watered more frequently).

Landscape contractors and clients who work together will create more water-efficient, resilient landscapes today, in order to be better prepared for a hotter, drier tomorrow.

For more detailed information, see University of Arizona Cooperative Extension Publication az1876: Drought and Extreme Heat: Plant Responses and Landscape Maintenance Practices  by Ursula Schuch.