Can’t get soil moisture to remain above 80%

Is it normal for the system to not water until the soil moisture drops below 10%? I originally had AD set at 50% but changed it to 20% to keep it regularly watered due to the heat. I thought setting it at 20% would cause the system to water after falling below 80%soil moisture. But it doesn’t. The attached pic shows my current set up in advanced settings. Let me know if I’m all backwards or what.

With Flex Daily (is that what you’re using?), Rachio will water when the Current Moisture Balance for the next day will be below 0" (0%). That doesn’t mean your lawn has no moisture; it means that none of the Allowed Depletion moisture is left. Your low Allowed Depletion of 20% means it will only water 0.16" at a time. Most of the country would use that 0.16" up in a day, resulting in watering every day. I don’t think you want that, but you do want it to water, and say it isn’t. Can you show a pic of your Moisture Graph and/or Table?

Where do I find that graph? And yes I run the flex daily schedule. Still trying to learn/understand this system. What are the best settings to use?

After selecting a Zone, click on the Soil Moisture % (you’re technically clicking on the little arrow to the right). That loads the Graph. Clicking on More Detail gives you the table.

Good to start out with the defaults, IMHO. Water delivered can vary a lot from the Nozzle Inches per Hour selected by the program, though.

Sorry, the table under More Detail will help a lot more. And if you could confirm your settings are the same, or if you’ve made any changes?

Sorry. I just put all zones back to factory reset. They were all at 20AD. Been reset back to 50AD about an hour ago.

The other question, is it normal for solid grass to go brown or dormant during hot temps, regardless of settings? Grass isn’t staying very green, except for two/three of my 7 zones

No, it isn’t, so watering in the past has been too little.

Let’s look at your new chart:

If your zone settings are as you originally posted, except you changed AD to 50%, the system should water 0.16" x 6" x 0.50 = 0.45". Your chart indicates it watered 0.46" today, so that’s close, and I assume it did water today. Looks like the schedule, or you, also watered 0.27" on the 25th and 0.77" yesterday (hopefully it did occur), meaning you are definitely “filled up” with moisture.

Assuming no rain for the next bit, and starting today with 0.81" of water in the zone (110%, the maximum), Rachio is saying your yard will dry out by 0.13" tomorrow, and 0.1" the next day. Let’s assume a 0.13" after that:

8/27: 0.81"
8/28: 0.81 - 0.13 = 0.68"
8/29: 0.68 - 0.10 = 0.58"
8/30: 0.58 - 0.13 = 0.45"
9/1: 0.45 - 0.13 = 0.32"
9/2: 0.32 - 0.13 = 0.19"
9/3: 0.19 - 0.13 = 0.06:
9/4: 0.06 - 0.13 = -0.07" if didn’t water 9/3
Since 9/4 would go below zero (inches or %), your system would water that zone on 9/3, or 6 days from today. Let’s continue, saying it did, and the 0.13 continues:
9/3: 0.19 - 0.13 + 0.46 = 0.52"
9/4: 0.52 - 0.13 = 0.39"
9/5: 0.39 - 0.13 = 0.26"
9/6: 0.26 - 0.13 = 0.13"
9/7: 0.13 - 0.13 = 0"

Since 9/7 would result in zero moisture or less, I /think/ the system would again water on 9/6, but it might wait until 9/7. With a constant 0.13 Crop Evapotranspiration, the system will water every 3-4 days, which is closer to the expected frequency (6 days above is from being oversaturated, along with cooler than normal weather.

You may think back on the heat we’ve gotten, and think that every 3-4 days isn’t enough, and you’d have been right earlier this week. CEs ran from 0.19 to 0.20, meaning your system would water about every 0.46 / 0.20 = 2.3 days. About every other day in hotter weather, it’s just been a bit cooler and more humid lately, so the soil loses less water.

Assuming your system is putting out the Nozzle Inches of water per hour that is selected (under Advanced settings), I think your system is probably adjusted okay now, and things should start greening up. But that Nozzle Inches per hour makes a lot of assumptions, and I think it can be a bit high (making your controller think you’re getting more water than you really are). If the lawn continues, in your opinion, to be a bit on the dry side, try /reducing/ the Nozzle Inches per hour, maybe by 10%, to increase watering time by 10%

Hope this helps. Let me know if you need clarification or anything else.

1 Like

Whew…mind is a bit blown lol. That’s a lot to sink in. I was thinking it wasn’t getting enough water as I believed I had the AD completely backwards and had it set at 80% so I switched it to 20%. It’s now at 50%. So the inches per hour setting is just the assumption by the system of what the head is putting out? Did I take that correctly? Would the installer put it at that rate based on the sprinkler head put in, or is that the factory setting for the specific sprinkler head that is listed in that zone? Simply decreasing the inches to .6-.63 would help by putting more water down?

Sorry for all the questions and confirmations. Clearly the system is high speed for me lol

You are not the only one who is confused about the settings. The fault is with Rachio using terminologies thats is not straightforward. Allowable Depletion? If you set AD at 80%, does it mean the minimum moisture level before triggering watering or does it mean let 80% moisture depleted (or 20% minimum level) before watering? I think instead of AD, “minimum moisture level before watering” would have been more clear.

I think that the problem is that Allowed Depletion is a standard irrigation term, and that many of us don’t take the time to learn the standard terms. Rachio is having to educate us on those terms. They have some write-ups in support pages that make it clearer, but it appears that they might need to make it even those easier for us laymen to understand.


That is correct. Rachio uses 3 different settings for lawns, depending on the type of sprinkler head. They may be valid values for a properly designed and implemented system, but come nowhere near my reality. I suspect that isn’t uncommon. But there’s little else they can do, outside of suggest some fairly complex or hard to do methods, and many people already think things are too complex. It’s a real Catch-22.

I think the /most/ any installer would do is set up the default values for you. Unless they have specific experience and information to the contrary, which is possible, I guess.

In your first screen capture, you have the system set for 1.25"/hour. That’s actually not a standard Rachio value for lawns (theirs are 1.0, 1.5 and 1.7, depending on the sprinkler head type). Decreasing the 1.25" to 1.0" would increase the watering time, and water, by 25%. Doing it in the Nozzle Inches per Hour will NOT change any graphs or table amounts. The total water it /thinks/ is being put down will remain the same. The frequency of watering will not change. It will all look the same, just with more water actually reaching the grass every time it waters. IMHO, it is NOT the best way to simply apply more water, but it is the best way to correct if the actual Nozzle Inches per Hour is wrong.

Hate to cause you extra work (and people get mad when I suggest anything that makes it more complex), but would the square foot area of each of your zones be difficult to calculate? If not, a test run for a known time, measuring gallons used, etc. is a great way of coming up with the above figure. I could help calculate areas if I had a Google Earth picture or dimensions. If that makes your eyes glaze over, just forget I mentioned it. :wink:

1 Like

@Linn you made it sound like we have to be “educated” to use an irrigation controller. Most of us bought the control for the “smart” of it, thinking that we could just set it and forget it. After buying it, we found out that we have to configure it correctly to work. Fine, we’d put it up with it. Then now we have to “learn standard irrigation terms” too? Who does Rachio think its average customer is? This is not high tech. Certainly Rachio could have looked at the UI from an average customer’s perspective and made it more user friendly. What they need is a study/focus group when it comes to UI design. Go to your customer’s level, not making customers go up to your level. That’s a successful business.

I’m not disagreeing at all that the UI could be even friendlier. But don’t we have to be “educated” to use a computer/mobile device properly as well? I know that I sure spend a lot of time helping my friends out, getting their devices to work as expected and fixing problems.

1 Like

I can get the square footage of a couple of my zones. Or at least the one that I have having more issues with. I don’t mind. I’ll take all the help I can get to understand this thing. I see if I can get it done tonight and be in touch with the numbers. Currently the one zone I’m dealing with is set at .61 inches per hour. Is that to low. I’m fairly certain it was originally set at .7 by either Rachio or my Sprinkler guy. Not sure. I decreased it last night by about 10%. Additionally, my lawn guy came by today and said that particular zone is really dry even thou it’s indicating a 86% moisture level. It is the zone you had sent all those numbers about. Which you were right, it was originally going to water again on 9/6, but now it moved it to 9/10. My lawn care guy was a bit concerned about that.

My perspective is that we buy a computer to be smarter. We buy a irrigation controller so we can stay dumb. I don’t think I want to spend hours on the Rachio interface (and I did!!!) like I would on a computer screen. If I had to do that, might as well go back to the old dumb Hunter controller I got installed initially with the system.

@jtuber You can always just used a Fixed schedule and then you don’t have to spend hours on the interface. Using a Rachio with a Fixed schedule still offers benefits compared to a dumb controller. You can adjust the watering in much finer increments and if you travel, or used to travel :slight_smile: you can control the watering remotely.

Sounds good. Be glad to help. I’m sure you can calculate some areas, but if you need any help on complex shapes, be happy to help.

I’d leave it alone for right now. Until we know more about the flows.

Then water the heck out of it. Fill 'er up! Water it today and tomorrow if you want. Doesn’t hurt, and knowing that your lawn is well saturated is a good starting point. You don’t want to /keep/ over-watering, but you want to start out with it full.

Oh, while you’re watering, either with a schedule or manual, try to take water meter readings to determine how much water is used in XX minutes for each zone. Might be best to water right now that way; no sense in wasting water later. Once you know the Minutes, the Gallons (read before and after watering) and the area for each zone, you’ll be in great shape.

At least the Rachio /suggests/ times, based on questions it asks. A manual controller allows YOU to set all the times, with no suggestions whatsoever. 10 minutes? 10 hours? Who knows? The really smart part of Rachio comes in after it’s dialed on, as it’s set and forget.