Flex Daily Schedule Issues - Dry Dry Dry

Hi All, I’m relatively new to Rachio and trying to really dial in my system for the summer. I have sod that was placed in July 2018 so it is now established but it has struggled the last two summers as I’ve worked to get the system dialed in and felt like I had to override many of the auto settings to keep the lawn happy. I really appreciate your expertise!

I am having a hard time with my flex daily schedule on all of my zones. I have done what I can to troubleshoot but am hoping you can help. See the attachment for screen shots to show my setup. I have found my yard very dry often. It seems as if the logic is off where it would allow my lawn to be dry over the course of two or more 80-90 degree days.

In short I have 6 zones, 5 are lawn, 1 is a combination drip/emitter mixed setup that surrounds my house for landscaping and a small garden area. In the attachment you can see the representative settings for both.

Issue 1 - My lawn has multiple zones with 0% soil moisture and is not scheduled to run until tomorrow and it’s going to be 90 today. That doesn’t make sense to me. It is on a flex daily schedule and I didn’t get any notice of a wind skip. See attached with examples of the setup. This is not an uncommon occurrance. The screenshots were taken a couple of days ago and now I’ve got a front yard zone with 3% soil moisture and "no upcoming watering and two other lawn zones at zero with nothing scheduled for today. What gives here?

Issue 2 - my landscaping is DRY. It is mulch with Clay Loam soil underneath. Right now my moisture says it is at 36%. It is not scheduled by the flex daily to water for another 12 days. If I put my finger in the bed it is dry to the depth that I can get my finger in. This is a different setup as it wraps my entire house and is mostly drip line with 1 GPH output and a few emitters in the garden area to fill in the areas between the drip line. I’m trying to dial this in but I cannot get to the right place to force the system to keep the beds at a reasonable moisture level.

Please see the attachment with my settings. I appreciate your help!

Rachio_200601.pdf (269.5 KB)

You have Tuesday excluded from the schedule. Is this on purpose?
Your total watering time is 8.5 hours ending at 5:40am, so the watering starts the previous day. So I think on June 2nd, no watering occurred because Tuesday was excluded, and then it scheduled watering on June 3rd. Maybe Rachio is not accounting for this very well.
I have switched to splitting my zones into two schedules with each schedule exclusively watering on certain days, and I am using the start time (1:30am) instead of end time (by sunrise). I find Rachio is anticipating the skipped day correctly, and would water the lawn even if it did not reach allowed depletion for that day, but it would have till next watering.

@cooonger Curious what your goals are?

Looking at the below zone settings (1/2) your root zone depth is widely varied (huge impact) and allowed depletion is changed from the default of 50%.

My recommendation is to move most zones to a fixed or flex monthly schedule, take one or two zones, reset the default values, and then only change watering minutes and crop coefficient (higher, water more frequently, lower, water less frequently). Get one or two zones dialed in, then roll those changes out to the rest of zones. We are working on much, much simpler scheduling (with learning) for next season if that helps extend your patience out :wink:

Similar issue here. It seems with each passing year the Rachio flex schedule does a worse and worse job of keeping things from drying out as we get into the hot months of the summer.

I will try to pose this as a simple question. If plants or lawn are drying out (leaves brown or wilting) is it:

  1. allowed depletion % too low (zone is drying out too much between waterings)
  2. crop coefficient too low (plants need more water or more frequently)
  3. nozzle precipitation rate assumed higher than actual

I think 3 is unlikely - I know the nozzles and have directly measured the flowrate and area per zone.

It seems like there should be some systematic way to know what to tweak and by how much.

I am irrigating what seems like a ton (and paying for it) but things look very dry, particularly in some zones. I just want what I have to look healthy. I am mostly using default settings.

I should add that I have the schedules set to start “at sunset” to avoid having Rachio get confused about what day it is. I do have one day with no irrigation so the yard isn’t wet when the gardeners come.

I don’t have an answer, but neither am I am sure if that’s the right way to look at the issue. There are four fundamental parameters that drive Rachio’s calculations:

  1. Soil’s available water
  2. Evapotranspiration
  3. Root depth
  4. Flow rate

So which of these can drift with time and get out of sync?

(1) can definitely change if soil isn’t maintained (i.e. no aeration).
(2) has two things packed into it, the reference ET and Crop Coefficient. Rachio get’s the reference ET dynamically. Is it possible the the source for this data has gone bad? (I don’t know if this is even possible). I believe the Crop Coefficient for grass is unlikely to change with time (it does for trees, for example, as they grow).
(3) While root depth can change, it will likely – short for some disease – change as a function of available water in the soil (so back to (1))
(4) Flow rate can definitely change as a result of city’s supplied pressure or if sprinklers are getting clogged up. But you said you’ve calibrated the flow rate, so this isn’t it (though, I hope you’ve calibrated it recently)

So at the moment my more likely suspect would be (1). Are you doing any regular soil maintenance?

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Hi @beranes. I was going to reply to this thread with same observation and ask about soil amendments. I have been calibrating my soil Available Water based on observations. I didn’t go through the exercise of testing it, so I am just relying on tweaking it and making sure it is not over field capacity when Rachio waters it to 100%.

I’ve had construction recently in my backyard which destroyed a large section of my lawn and compacted the soil. To restore the lawn, I hired someone to come and rototill the soil and spread compost. They didn’t use topsoil, and instead added 3-4 inches of compost on top of the soil. They swore that this works. So grass is growing. But the soil is spongy, and I have had to reduce Available Water in order to reduce watering that makes the compost spongy. Compost holds a lot of that water.

So a good soil amendment that improves its water capacity and make it more resistant to drought periods is to add a thin layer of compost after core aerating the lawn. Compost retains more water and will improve water capacity. Spreading a thin layer on top of the soil won’t make it spongy like mine, but will help break down compactness in soil over time, and improve its water capacity. And you won’t need to water as much between watering periods.

Assuming you’re using the defaults (standard) values for your grass and soil, I would normally suspect #3 is off, based on my experience. But if you have actually measured it with flow and area as you say, then you should adjust the Crop Coefficient. Increasing it will increase the water applied to the zone. Simple as that. Most of the other factors determine how much water is applied at one time (and therefore, how often it is applied).

Thank you for the response.

My lawn zones have a crop coefficient of 85%, so already pretty high. I’m going to try lowering the allowed depletion.

I have a mixed tree/shrub zone that is really vexing. I will try raising the crop coefficient.

In terms of precipitation, my utility water meter is digital and one of the cool displays is flowrate. So I can just run each zone and read the flow rate off the meter. That divided by the zone area is the precipitation rate with some unit conversion and allowance for water spraying outside the zone (I don’t have much of that).

That won’t apply more water to your zone over time. Lowering the Allowed Depletion will simply water less at one time, meaning your system will make up for it by watering a little more often. Changing Soil Type, Root Depth and Allowed Depletion all only determine how much water at once. To get more water over time for a lawn lacking water you should increase the Crop Coefficient. Going from 85% to 100% is a substantial increase. The other way of doing it would be to lie about your Nozzle Inches per Hour, but I really hate to do that, as you know what it is (most don’t).

Thank you. That makes sense and is the kind of input I was looking for.

You are assuming what my problem is is too little water, not getting too dry/stressed between waterings. A good assumption, but is there a way to test it?

For now I increased the crop coefficient for the suspect stations by 5% and returned the allowed depletion to the default 50%. We’ll see.

I don’t think this explains why things get progressively worse year-over-year.

Correct. Once dialed in, Flex Daily should be fine in all weather conditions. Either something has changed, or it was always a little low (but tolerable) and more recent hotter than normal temperatures has exposed the problem. If watering occurs every day, it’s also possible longer run times are needed.

That is what I would think; the whole point of the Rachio is to make adjustments for actual weather. I have downloaded the historical data going back to when I installed the Rachio and I have my prior manual schedules, so I can compare actual irrigation year-to-year, both volume and interval days. I am not sure if I can layer in the actual ETo data. I do think my landscaping does not look as good as it did the first Rachio year.

I’ve had my Rachio for over 5 years and on Flex Daily since the day I installed it, and I’ve noticed no difference in the performance of my Rachio. There may have been some backend tweaks over the years, but I haven’t seen it affect performance in any way.

Now, I do maintain the heck out of my irrigation system though, checking spray heads, cleaning/replacing them if needed, replacing drip emitters as needed, repairing/cleaning/rebuilding valves as needed, and checking system for leaks regularly. Also, not that we get a lot of rain here in Arizona, but I check the PWS that I’m working from to make sure that it is supplying my Rachio’s with accurate data.

I think that one thing that can explain a difference in performance from one year to the next is the weather. I’m not sure we ever get COMPLETELY dialed in with any sprinkler system (unless you’re over-watering), so a good heavy but gradual rain, like the 1.31" we had last night, “resets” the system. Everything is watered fully, and deeply, and Rachio knows it. Having just a little rain every so often does not do that. Rachio allows for it, but if there’s errors, they just keep creeping up. Anyhow, that’s my thought.

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I could agree with that. If you are looking to save every last drop of water you can, you could certainly running on the edge. Adjusting the crop coefficients a tad to give a little buffer could be helpful to some.

Is there anywhere in the US where there are no major rains year around? Sure, the error could creep up through a dry season, but winters should always be “resetting” it back. Here in Sothern California even in the driest years we still have enough rainy days in Jan/Feb to reset soil moisture.

I doubt the grass would make it to winter if it’s running a bit dry in irrigation and has no rains to reset. Continually watering somewhat less than necessary would dry out the lower 50% of the soil we consider to always be damp, preventing roots from going deep and making it very susceptable to extended dry/hot periods.