Soil moisture estimates too high

I’ve been using a Rachio 3 for a couple of weeks with Flex Daily, and the zone soil moisture estimates are laughably high: sometimes in the 80s for nearly dry earth. The zones are scheduled to be watered only every couple of weeks. I live in Seattle, which rarely gets rain this time of year.

Why does the controller think the soil is retaining water for so long, which I assume to be the problem? How do I correct this?


What are your Advanced settings on your zone(s)? Until Rachio is connected to your system and zones entered (and it will then be reading local rain and such), Rachio has no idea about the moisture. And if you get little rain, it will know less. You can’t always do this, but it’s great to start Rachio after a long soaking rain which you feel has saturated the soil, and set the zone to Fill. A way for Rachio to do this for you (although it will waste some water at first) is to set the zone to Empty. Rachio will then fill it up, and hopefully keep track more accurately after that.

That said, it could just be new settings for a new yard, so it would be good to know those.

Thanks, I found how to set to Empty, which is about what the zones are right now.

I also discovered how to calculate Nozzle inches per hour, using zone area and total emitter GPH. That produced a much lower figure than the default, which I suspect was the main problem.

It would be nice if Rachio asked for the total flow for an emitter zone, and performed the calculation automatically. Did I miss that somewhere? Also, since emitters are targeted, calculating the area of a zone is problematic, In fact, I’ve never had any idea how much water “bleeds” beyond the plant root areas.

I expect that I will end up adjusting Rachio’s parameters according to the results I see.

Agreed. When you say “total emitter GPH”, you’re referring to the total GPH for ALL the emitters in that zone, right? If so, yeah, that’s correct.

I’ve always had a problem with my one shrub zone watered by emitters. Wish I’d never removed the soaker hoses the builder put in, which pretty much saturated everything.

What I did with my emitters (prior to Rachio) is to add up all the gallons of water all of my shrubs and such in the emitter area needed per week, then measure my GPH flow to that zone, and from that calculate how long I had to run the zone to get that number of gallons. This assumes your emitters are located properly, with more or larger emitters for larger bushes, but should get you the water you want. Of course, that varies from month to month, hot weather to cold. I fudged some figures into Rachio for my emitter zone, and it’s coming up with times about 15% higher, with lower frequencies, so I think I’m in the area. Just bought a moisture meter, and hope to try to work with it to get better answers.

My emitter zones replaced miles (it seemed) of Netafim dripline. The dripline clogged over time, and since it was buried I couldn’t even tell what sections were still working properly. Emitters solved that problem, but they can pop off, which creates a mess. Thus is life.

Your use of the word “fudged” anticipates what I was going to add to this thread: It would be nice if Rachio allowed users to measure actual soil moisture and input that data while Rachio was training itself. Then, the controller could adjust how it thinks it should irrigate based on the supplied parameters, with how it actually needs to irrigate. I find it hard to believe that users can accurately specify all but the simplest irrigation zones, and you really don’t want users faking the parameters in order to get the desired results.

My soaker hoses, and now my emitters, are not buried, but they are under landscape fabric, and are hard to locate, harder to see if they’re working. I hate them all, and am tempted to put in sprinkler heads.

Some can be pretty well determined, but yeah, others are a real shot in the dark. I got a decent soil moisture gauge, but anything but the most expensive are relative moisture (mine can be calibrated). And while it /says/ it measures just at its 14" tip, it doesn’t seem to vary much when inserted deeper. I don’t think I can rely on it to determine when to water. But yeah, I’d love to see an active moisture meter that would really tell us when to water. Until then, we all get to become amateur soil, rain and crop experts to try to understand all this. My Aerospace degree doesn’t help me much here (“Why, yes, as a matter of fact, I /am/ a rocket scientist! But /this/ is something else!”).

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