Improving Rachio's calculations

Hi everyone!
I had a really bad summer with my Rachio and Flexible Daily Schedules. I went and measured each zone, did audits of the rotors, and did soil mason jar tests for each zone (they all came back the same: sandy loam). However, I still ended up with dry, brown grass and dusty barren patches of soil. Is there anything more that I can do? I’m considering adding Rainbird SMRT-Y moisture sensors, but at $150 each, that’s $1200 for 8 zones assuming that I DIY the installation.

Can you help with some more details. What type of lawn do you have, and where do you live? Maybe add screenshots of advanced settings and moisture graphs, and a couple of pictures of you lawn’s problem areas.

That’s a great idea! Sorry!!! I’m in Long Island, NY

Pictures are a bit hard because I’ve spent the last month reseeding different areas and putting them on a manual schedule, but I’ve attached photos of four different sections of my lawn. Most are full sun, with the exception of the area in front of my house, which is part sun. It’s west facing though, so it gets absolutely blasted in the late afternoon. The area with the wide shot was the most painful: it was pretty much all dirt two weeks ago.

I don’t know what has happened to the graph and the little hydration monitor. Maybe it went away when I disabled the smart schedule and created manual schedules?

Any suggestions you might have would be appreciated.

I’m not necessarily recommending the sensors as a solution but I have 6, maybe 8 of them for sale. They are new and I got them from on close out from a dealer for cheap, by cheap I mean free. You usually only use on of them and place it in an average area of the yard. They could at least give you more data to use. I would go $10 a piece plus some shipping.

I’ll take 2.

@jasonjacobs Would you be willing to sell a couple more to me?

I am having similar problems and I think they would be a great help, which sensors do you have?

They’re the Rain Bird SMRT-y sensor kit. Just private message me your email and I can invoice you with paypal.

Do you have any more sensors you want to move? I would be interested in two.

Did you get my PM?

FYI, you need individual common wires for each SMRT-y sensor. Not going to work if you put one on each zone.

I would say before you spend money on stuff, you try to find out why exactly the grass died. Grass can die from overwatering just as easily as underwatering. Was the soil exceptionally dry in the dead areas? Is your grass species susceptible to disease or insect attacks? On your area of Long Island, is salt spray from the ocean a possible factor?

One thing I adjust with abandon on my Rachio is the soil type. I find it is utterly irrelevant what your actual type of soil is. If you have sandy loam and it is drying out too fast then change to the next type - loamy sand, or even sand. This will cause Rachio to water more often. You can also change other setting to get more water on the lawn - if in fact that is actually the problem.

Did the audit reveal good head to head coverage?

I’d start with that first before purchasing anything. The troubled areas may be fixed with just some nozzle adjustments or different nozzles.

Yep! Using the orbit cups, I was getting between 50-80mm of water per hour, exactly as expected. This is a brand new set of Hunter I-20s: we dug up the yard last fall and redid EVERYTHING.

How do you suggest that I measure the hydration level? My thought is that especially in those areas, it was too dry. I’m not near the ocean, so wasn’t that…

So, if the coverage is good, why are you getting “dusty barren patches” in the yard? Something seems out of balance if some areas are drying out faster than other areas.

Are the I20 nozzles matched?
For example: Quarter- 1 GPM, Half- 2 GPM, Full- 4 GPM

If you’ve already done the audit and know the PR, maybe just increasing the frequency in those areas will fix the troubled areas. Sandy loam would need more frequent watering.

Welshdog has some good insightful questions and observations.

Well, just because the sprinklers are capable of covering the zone with an inch of water doesn’t mean it is. If Rachio calculates the soil is 70% hydrated, it may choose not to water or to water only a little. If the reality was that it was only 20% hydrated, then it would have made the wrong choice. That’s the simplest explanation.

Likewise, if Rachio thinks that by watering for four 15-minute periods, it will go from 40% hydrated to 60% hydrated, but the reality is that it goes only to 45% hydrated, then again, it made the wrong choice. That’s also a somewhat simple explanation.

There’s also the possibility that there is simply some sort of disease in that area: cinch bugs, Brown patch, etc, that is killing the grass and giving the illusion of dehydrated soil.

So it comes back to:

  1. how do I measure the hydration of the soil to verify Rachio’s calculation of “before” moisture.
  2. how do I measure the hydration of the soil to verify Rachio’s calculates “after” moisture.

Assuming one or (more likely) both of the above is incorrect, then how do I feed the info back in to / correct Rachio appropriately?

Calculate the zone area SF.

Run the zone for 1 minute note the gallons used.

Make a custom nozzle and name it for that area.

Anything else is just guessing.

Anyway it has been working for me.

I did zone measurements for each zone.
I also measured the square footage, and did mason jar soil tests for each zone.
Glad to hear it’s working for you. I’m unhappy with my results… but as I said, I don’t know if that’s Rachio’s calculations or something else.

The pictures help, but if you post the screenshots mentioned above it would help. Also include the precipitation rate you use for the nozzles.

I think you have multiple issues going on, related to both Irrigation and soil fertility.

Looking at those pictures and it’s very apparent that your soil is too dry. On average how many minutes a zone were running and how often? How about head spacing? Are you on a well or municipal water? Nozzles? How many heads on a zone? How about a rain sensor? Do you have one properly placed and working? Or, are you relying on Rachio to do it.

Now on to soil. What’s your pH? How about potassium levels? How much N do you put down? Cation exchange capacity? How thick in inches is your topsoil layer? Was it brought in recently? Any compaction? Can I easily get a soil probe into the ground.

Now on to cultural. Are you taking into account the trees and shrubs in or adjacent to your lawn zones? They will suck up most, if not all, the water you budgeted for lawn.

Soil moisture sensors are a great addition to any system, but you really need to know the answers to all of the above.

If you don’t know, how is a computer in Colorado supposed to?

If you want to discuss further, send me a pm. I am on LI and I do this for a living and would be more than happy to help you out.