Desert Ficus Watering Volume?

Question

Watering a ficus grown in Phoenix, AZ, I've recently had irrigation put in that has changed the way I water the tree. Previously I just used a hose and ran it at lower volume output for an undetermined amount of time, filling up a circular berm we had formed around said tree.

With the irrigation, I have no idea what I should be doing. I found a document made by Arizona Municipal that recommends 24-36 inches of depth, every 7-10 days, but don't know how to measure that depth.

It's an Orbit timer, and I currently have it set to 30 minutes a day. The tree is about five inches in diameter.

Thanks in advance!

Answer 1

Measure moisture depth by getting a metal or wooden rod about 1/4 inches in diameter and pushing it gently into the moist soil. When you feel the resistance change or stop, try a few more times in a few other places to make sure it wasn't just a rock. Measure the distance you were able to push the rod before the resistance changed. That is your watering depth. If it's too short or too long, adjust accordingly.

Every 7-10 days is a really long time to wait between waterings for a ficus in the summer in Phoenix, especially if the temps are over 105°F. You're probably looking at closer to 3-5 days in between, and even more if it's in full sun or over 110°F.