Q.How to determine water needs for citrus trees using drip system
Live in Phoenix area. Trees are not fully mature but not babies. Installed drip system and installer said run system 6 minutes every day at 1 a. m. There is a bubbler in the well for each tree. There are 2 lemons and 1 tangerine, which produced fruit last season. How can I be sure they are getting enough water? We will be gone for the summer. Can you help me?

Certified GKH Gardening Expert
The rule of thumb is 2" of water per week. Since you are on a drip system, I would recommend taking one of the lines out of the ground and measuring how long it takes to fill a small cup to 2". That will determine how long to run the drip system for proper watering. Since you live in a much warmer climate, I would water two times a week for at least 15-20 minutes (longer if it has been very hot and dry) so that at least 2-3" of water go in the soil every time you water. This will encourage deep root growth, which will help it survive in the higher temperatures.
Here is more information:
https://www.gardeningknowhow.com/edible/fruits/citrus/tip-on-water-requirements-for-citrus-trees.htm