Why is the Rachio app recommending 1/2 the water UF recommends?

I created a custom nozzle with a 1.1 inch/hour precipitation rate and applied that nozzle to a zone with warm season grass, loam, some shade, and a flat slope. When I created a Watering Time the app suggested a 17 minute run time for that zone. I believe that would result in 0.31166 inches of water being applied to my grass.

I have St. Augustine Seville and UF recommends between 0.5 and 0.75 inches per application, http://edis.ifas.ufl.edu/lh010. So why is Rachio calculating such a short run time? I know I can manually increase the run times but I imagine it is better to work “within” the system if I want to utilize all of the automated features Rachio provides. Any suggestions or explanations?

This morning I deleted the old Watering Time and made a new one that now suggests a 30 minute run time. I think I’m using the same zone and nozzle data but perhaps I inadvertently change something? I’m still a bit curious about the run time calculations but I suppose my problem is solved.

I did notice one oddity/bug during all of this:

  1. Associate a “low” flow nozzle with all of your zones.
  2. Create a Watering Time and you’ll get a “long” run time.
  3. Modify your zones to use a “high” flow nozzle.
  4. The Watering Time does NOT update the run time, you still have a “long” run time.
  5. Delete the Watering Time, create a new one from scratch, and you’ll get a “short” run time.

@EdLaFave, Good morning, great questions. Sorry for the delayed reply.

I think you might have hit it on your second post.

At this time, the watering times are static to the zone settings at the time the watering time was created. They are not dynamic, in that they change should you adjust the zone settings. We are working on correcting this :wink:

Back to your scheduling question:

Has this been addressed and fixed with the zone settings adjustments? Or would you like me to double check your account for any weirdness? Let me know how I can help.

Best, Emil


No need to look into this any further because the app is now suggesting reasonable run times.

I suspect this is what originally happened:

  1. I configured my zones to use a high flow nozzle.
  2. I created a Watering Times but didn’t really look at the run times assigned to each zone.
  3. I switched to my 1.1 inch/hour nozzle.
  4. Then I inspected the details of the Watering Times and was confused by the short run times.

Knowing that the Watering Times aren’t dynamic explains this behavior and the fact that deleting and recreating the Watering Times gave me appropriate run times.

It is worth noting, for anybody reading this thread in the future, that although run times don’t automatically update when you change the nozzle that doesn’t seem to be the case for the cycle/soak feature. After creating a Watering Time I modified some of the features that would impact the cycle/soak feature (nozzle, grade, and soil type) and the application responded by adding/removing cycles based on my changes.