Clearly cannot figure out Flex system (Los Angeles)

Okay, so, I realize I might be dipping my feet into a system that’s too complicated for my rather modest understanding of home watering systems, but here’s the general overview of my situation:

I have a very small yard (<1000ft) in Los Angeles with pretty dry, arid soil. I have a few plants and I would love to set up my Rachio on a daily schedule so that it can appropriately plan based on heat / dryness that is so prevalent in Los Angeles. I spent a few hours reading the Rachio documentation and trying to set up the Daily schedule and have now completely flummoxed myself.

For reference, so far I’ve been watering ~12-15 minutes 2-3 times a week and everything has been handling that pretty well. Given the water shortages in Los Angeles, this is about the maximum you’re supposed to water per week. After setting up the system in the Rachio, it suggests:

2hrs,54minutes of watering per cycle. That’s more watering, in one day, than I would do in an entire month of my normal cycles.

I absolutely cannot figure out how to get this set up to a more normal system. I understand that you’re supposed to “overwater” originally in the Flex system, but this is absurd and would also incur massive fines from Los Angeles county.

My relative lack of knowledge about watering systems is probably at fault here but I don’t really know how else to approach this. Does anyone from LA county (or similar climates) with dry soil have any suggestions? I’m trying to work this out but it’s hardly simple.

Thanks a bunch.

@syntheticpathos I usually recommend that people start with making sure their soil settings are reasonable. If you haven’t already taken a look at the Web Soil Survey, check out this post to see if it helps.

After that, you’ll want to look at the nozzles attached to each zone, to see if they are an accurate reflection of what your system is really providing for a rate of water delivery. You can post the nozzles you use per zone, and associated precipitation rate (in/hr), and folks will chime in here to help.

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@azdavidr Okay, I’ve followed your Web Soil Survey procedure (which was super helpful, by the way!) and it’s come back as Loam with 0.16 available water across the board, which was surprisingly not that far from what I had guessed at.

Here’s a photo of the nozzles I have. I’ve guessed that as a Bubbler type, but that’s a total guess. And, obviously, thank you so much for your help!

@syntheticpathos Pick one of your zones, maybe the one with the nozzles that you took a picture of, and include screenshots of your settings, including the ‘advanced’ settings. Also go to your zone and look for ‘Moisture Levels’. Open that up, then expand the ‘Details’ and ‘Irrigation’ section of the table. It will show something like this.

This will give a good idea of what your system is trying to do based on the parameters that you have set up.

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Here’s the zone set up, currently:

And here are the moisture levels – though uhh they’re pretty barren!

@syntheticpathos On the Allowed Depletion, did you intentionally change the ‘Allowed Depletion’ to 30% ? That should normally stay set to 50%.

It doesn’t look like your Flex schedule is reflected in your Moisture Graph, but some other schedule is. You can see that under ‘Other Schedules’, whereas nothing is listed in the ‘Flexible Daily Schedules’ row. What schedule do you have enabled ? Is your ‘Flex Daily Schedule’ disabled ?

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Ah, yeah, I accidentally set that to 30% in order to see if that would change anything. Sorry! I totally forgot that I did that. It obviously gets worse at 50%, but the original numbers I quoted were before I set it to 30%.

Yeah, that’s because I can’t activate the Flex Schedule since the first watering would VASTLY blow out my water usage for the month. Right now I’m just using a Fixed Days schedule since I can’t get the flexible schedules to give me numbers that make any sense :frowning:

@syntheticpathos Go ahead and temporarily enable flex, and disable the other schedule, then take a snapshot of the Moisture Levels table. It will go a long way in figuring out what Flex is trying to do. You can then go back and disable Flex and enable your fixed schedule.

Ah, sorry! Here you go.

@syntheticpathos That’s looking better. Please expand the ‘Irrigation’ tab, and then forward to the next couple of weeks and post snapshots of those as well.

Okay! Here’s the Irrigation tab expanded and the next two weeks out, as it won’t let me predict outside of that range.

As aside, thank you so much for all the help. It’s pretty unbelievable how helpful you are!

If you’re using the default ‘Bubbler’ nozzle, then it assumes that your irrigation is putting down 1" per hour. Since your moisture graphs are showing that 1.2 inches of water is the target, and you have an efficiency of 90% defined, your watering time must be around 1hr 20mins. Is that what you see when you go to your schedules and poke around for the Flex schedule associated with this zone ? I’m not sure if that’s what you expect or not, but note that it’s only watering every 10 or 11 days.

It seems to me that flex is trying to water much more deeply, and less frequently than your previous fixed schedule of 15 mins every other day. When you think about an 11 day span watering every other day, you’re watering for the same amount of time. Watering deeply and less frequently is what makes good drought tolerant vegetation that ultimately consumes less water.

Check any other zones for the same behavior. What types of vegetation do you have in each zone ? If you’re going to move to flex, there are things you can do to transition slowly. Otherwise I’m worried that you’d stress out your plants, as they need time to develop deeper roots in order to survive that 10 day dry spell.

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Yeah, I was noticing exactly the same sort of thing. Zone 2 was the one you’ve already seen. So, after checking the other zones:

Zone 1: Mostly the same type of plants and the predicted behavior matches Zone 2 almost exactly. There is some ivy-type stuff here, too.
Zone 2: You’ve already seen this one.
Zone 3: This is more small tree / shrub types with a significant slope grade, and it is a much more frequent, saw-tooth type watering plan alterating every other day. So, day 1, nothing. Day 2, watering about 20 minutes, day 3 nothing, etc.

Looking at the predicted schedule overall (all three zones), when we step into late September/early October, September 30th is 76 minutes of total watering, October 2nd is 45 minutes, October 3rd is nothing, 4th is 45 minutes, 5th is 61 minutes.

Again, these total values would blow my water bill completely.

When I compared Zone 2 to your current ~15mins every other day, the total over the 11 day period was the same for total water. If the other zones are similar, then why would this blow out your water bill ?

FYI, something is off with Zone 3 compared to #1 & #2. Plants should water more often and for shorter duration relative to trees. Check your root depth and vegetation type for all of the zones, ultimately making sure the plants get watered more frequently than the trees.

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Ah, my mistake – I was looking at the wrong thing. Sorry. It looks like Zone 1 is planning to water every 3-5 days, which makes sense with the numbers we were seeing in the last post. So, Zone 2 is every 11 days, Zone 1 is every 3-5 days, and Zone 3 is every other day.

So, what’s your recommendation to get my plants more used to more intense, less frequent watering cycles? It SEEMS like my numbers are not horrifically off (I think the variance between Zone 1 and 2 is due to shade amounts).

Sorry for being such a pain here…

No worries. I’m still confused about zone 3. If zone 3 has trees and shrubs that would have deeper root systems than what’s planted in zones 1 & 2, then zone 3 should have the longest spacings between watering. However, you say it is cycling on/off every other day? If nothing stands out to you post a screen shot of the zone 3 settings (advanced too) and the Moisture Graphs/Tables.

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Okay. Talking to you has gotten me to a much better place, examining the types of plants I have and exactly what category they should fit in. I’ve fixed up the Zone 3 type from Trees to Perennials, which I think is more accurate (it’s a bit mixed-use, unfortunately, but the few tree-like things are the odd ones out) and that’s looking much more reasonable. Now the projected watering schedule for Zone 3 is 5 day break, then a 7 day break with about 30 minutes of watering per set, which seems much more reasonable to me.

Unfortunately I’m still seeing more water use than I would like, but it’s much less catastrophic than it seemed before. Now I’m looking at:

Sept 26: 100 minutes
Sept 30: 30 min
Oct 1: 150 min
Oct 2: 40 min
Oct 5: 30 minutes

As you can see, it’s still prettttty bad, but much less (about 30% less) than it was.

Looking at the detailed lists for each zone, it appears as though the contributions from each zone (for example, for Sept 26) would be (irrigation in inches)

Zone 1: 0.48
Zone 2: 0.64
Zone 3: 0.56

I’ve attached the screenshot for Zone 3 and the prediction for next week.

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Ok, you’re coming up to speed now and diving deeper will get you to where you want to be. That 10 inches of root depth seems a bit deep for a perennial, but given that I don’t have any I could be wrong. :wink: Deep roots mean longer watering. The other factor is ‘crop coefficient’, which defines how quickly the vegetation in your zone consumes water, thereby needing to be replenished again. I highly recommend you take a look at this article. Note the table where they give you the trade-offs between root depth and watering duration and frequency, as well as a bunch of other stuff.

Once you get to where you know what your settings should be, circle back to think about where you were before. For example, if your new schedule says you need to water 40 minutes to put down the 0.5 inch of water required for say 24 inch roots, but you were only watering 15 minutes a day, your roots are likely not that deep. In that case, the way to ease into the correct schedules is to drop your root depth to a lower value, until your run times are closer to say 20-25 minutes. After a few weeks, bump the root depth up an inch. Stay there another few weeks, then bump up again. Keep going until you get to the root depth that your plants should have.

Another big variable to your run times is your nozzles. Don’t neglect this, as the directly impact run time. For example, you have ‘fixed spray head’ in your snapshot above (you say Zone 3, but the snapshot says Zone 4). Is that snapshot for a lawn? If so, it should say ‘Warm Season Grass’ or ‘Cool Season Grass’. If it’s not a lawn, then I’m not sure if it should have a ‘Fixed Spray Head Nozzle’.


Oh, man. Every single time I feel like I’m getting a handle on this, the complexity spirals out again. Well, it does appeal to my engineering side, that’s for sure.

I can’t really get a grasp on what type of nozzle I do have, but I think you’re right that the Fixed Spray Head Nozzle isn’t the right one. I don’t think they’re Bubblers, but if I set them to Bubbler then the watering frequency comes out at a length of time I think is just about right. So, hey! I think I’m almost there! All my actual settings may be objectively wrong but they’re starting to come out in a way that makes more sense.

Okay, I’ll try to fiddle with the root depth and the crop coefficient for the next few weeks and see where I end up. This is just great. Thank you so much for your help! I may be coming back here in the future, but I do think like I’m getting closer to where I want to be…

The last question I have, I guess, is there any forward notification system for Flex schedule? Just to, like, make sure it’s not going to decide that it needs to water for 6 hours in one day? Or should I just continuously check the app / website until I find some measure of reassurance?

Thanks again!

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Keep in mind that the only times your flex durations will change is when you make setting changes. Flex only changes the days between watering. Having said that, definitely keep an eye in your moisture graphs, and your vegetation? Take a short stroll around the yard to see how things are holding up between waterings. That way you can see of plants are showing signs of stress before it’s too late. If that’s the case, start a manual watering of the same duration as your flex schedule then consider either dropping you root depth or increasing the crop coefficient. If your trying to make the transition to drought tolerant plants with deeper roots, leave the crop coefficient alone and drop the root depth for a while, but notch it up again later.

Glad to hear that you’re engineer. It helped me figure all of this out!