UC Davis CA&ES

photo by Loren Oki

Drought Messages for Landscape Managers

This resource for landscape managers includes hyperlinks within the text to more comprehensive references. An extensive list of drought resources and supplementary information for landscape managers and home gardeners can be downloaded here. If you have additional resources to add to this list, please contact us at .

Reduce irrigation.

Provide only as much water as the landscape requires [1] [2] [3] [4]. Most landscapes are given too much water and can flourish on less. Over-irrigation can actually predispose plants to other problems.

Prioritize the plants that will receive water.

During irrigation restrictions, select those plants that will receive the limited amounts of water available for irrigation. One way to determine this is to think about which plants can tolerate limited water [1] [2] or are more easily replaced. Lower priority plants may be removed from crowded areas to further conserve water.

Plants may look different under water stress.

Plants will respond to water stress in different ways but can recover. Recognize water stress symptoms to determine how long plants can go without irrigation [trees, turf]. Adjust expectations of plant performance during drought [turf (1, 2, 3)].

Irrigate efficiently.

  • Optimize your irrigation system with regular system checks, including full audits [turf].
    • Make sure that you know what each valve controls: what kinds of emitters (sprinklers, drip, etc.), how many there are, and the plant types in each zone.
    • Make sure that each zone is performing as you expect: make repairs properly and in a timely manner; adjust sprinklers as necessary; replace plugged drip emitters and repair leaks quickly.
    • Change older sprinklers to newer water efficient ones – check for rebates offered by your water purveyor. Replace spray heads with rotary stream ones (e.g. Rain Bird RN or R-VAN, Toro PRN, Hunter MP Rotator, Orbit Eco-Stream) that deliver water at lower pressure and flow rates.
  • Switch to drip [1] [2] [3] [4] or subsurface irrigation where appropriate.
  • Utilize technology such as smart controllers [1] [2] and soil moisture sensors [tensiometers].
  • Schedule irrigation quantity and frequency to match the needs of the landscape [1] [2] [3] [4] [5] [6] [turf; lawns in heavy soil] [drip for woody plants, p. 3] [fruit trees]. Adjust the program in your irrigation controller at least monthly as the weather changes to better match plant needs.
  • Water deeply and infrequently to discourage shallow rooting, without allowing too much water to move beyond the root zone [lawns, woody plants].
  • Eliminate runoff by irrigating in cycles and replacing and/or adjusting sprinklers that irrigate hardscape. Understanding soil properties can help [1] [2].
  • Manage irrigation for microclimates within your landscape [lawns in shade].

Pre-condition your landscape to enhance survival during the drought.

  • Slowly reduce irrigation volume if adjustments have not been made earlier in the season [turf in drought].
  • If plants enter dormancy, maintain deficit irrigation or recovery will be impacted.

Use cultural practices that promote water conservation.

  • Make sure plants within a hydrozone have similar water use requirements.
  • Promote soil health to improve infiltration [grasscycling (1) (2), mitigate turf compaction].
  • Cover exposed soil surfaces with mulch [1] [2] to reduce evaporation and suppress weeds [lawns].
  • Reduce or eliminate fertilizer input to curb excessive tender growth [lawns, trees].
  • In severe drought, prune back large, wilted plants to reduce transpiration.

Manage for salts.

Avoid frequent shallow irrigation that concentrates salts at the soil surface. If irrigation is not restricted, water beyond the root zone to leach away salts.


Contributors

  • Dave Fujino, CCUH, UC Davis
  • Darren Haver, UC Cooperative Extension
  • Loren Oki, UC Cooperative Extension
  • Jennifer Tso, UC Davis

UC ANR Logo  CCUH Logo    UC Davis Logo