Good advice from the City of Temecula:
1. Water mature trees 1-2 times per month at the edge of the tree canopy – NOT at the base
2. Water young trees 2-4 times per week
3. Shower with a bucket and use that water for your trees
4. Do not over-prune trees as it can cause them stress
5. Use 4-6 inches of mulch to help retain moisture, reduce water needs, and protect your trees
Get more tips here:
https://www.ranchowater.com/Checkyourwater