Flex Daily seems to be overwatering my tall fescue (Maryland)

Hi everyone, I’ve been a browser of the community for some time now but wanted to reach out for some help with changes I made to my setup.

I’ve been using the Gen 3 model for three years now and am overall pleased.

My issue recently is that I feel as though my irrigation is running more than it truly needs to. I have always used Flex Daily and last season, I took time to fine tune my settings to what I thought they should be. My results are great but I fear for my water bill.

Year 1 I did a basic setup for my yard by identifying the grass type and amount of sun only. The following year, I got a soil test, measured my zones, and estimated my irrigation per hour. What’s frustrating now is that Rachio seems to be every day right now different zones here and there. We had a good amount of rain at the beginning of the month which really saturated the ground. Rachio kicked in again maybe a week after the storms and is now back to acting as if it’s the dead of summer (temps remain mid 80s still).

I’ll list my settings below and hoping someone could advise me if I should change anything. I’m tempted to go back to default for everything and start over. I would really like to reduce the frequency of waterings (especially the back) so that they are infrequent and deep waterings. Then again maybe I’m overthinking it and I should accept the fact that the summer months require more water. Thanks!

General Info

  • Location - Maryland
  • 8 zones - 4 front yard (Flex Daily Sunrise) and 4 back yard (flex sunset as needed)…I care way more about the front so I would be OK if the back was skipped more.
  • Turf - Tall Fescue
  • Soil - Sandy Loam (I paid for a soil test)
  • Spray Heads - Hunter PGP (#8 or #9 not sure) - each zone has 3 or 4 nozzles and runs at about 4.4 - 4.8GPM (per flow meter in the app)
  • Exposure - Lots of Sun/Some Shade (no tall trees around only shade is from surrounding houses)

Advanced Changes (represents almost all zones)

  • Available Water - 0.12 in/in
  • Root Depth - 4.5 - 5.0in (new construction home, sod placed in late 2017)
  • Allowed Depletion - 50%
  • Efficiency - 80%
  • Crop Coefficient - 80-85%
  • Nozzle inches per hour - 0.40 - 0.50 (based on tuna can test)

Also worth mentioning - I stay on top of my fertilizer and routine applications throughout the season.

Your settings all look fine to me. The reason it waters more frequently is your sandy soil, which can’t hold as much water as some other types. You might be able to lower your crop coefficient some, and save some water. Online I see 50-80% CC for Tall Fescue, and you’re running 80-85%. So if you want to save some water, maybe drop the front yard to 70%, back to 60%, and see how that works for your grass. The good news with Tall Fescue is the extremely deep roots that will help you through dry times (but still use the root depth you have for irrigation purposes).

Well, that’s a given. Your yard will definitely require more water in summer. But you can possibly reduce it a bit.