Why does it water starting at 5PM?

Hey all, I’m trying to let the Rachio just manage itself, hoping to have a lawn that isn’t dead and doesn’t cost me a paycheck every month. I have installed MP Rotator heads everywhere. 7 zones, a lot of clay loam, and I’ve manually set each zone to 0.4 inches per hour to match the heads. Rachio is set to flexible daily, “As needed, finish before sunrise”.

I’m not sure things are right… the schedule says the watering duration will be 682 minutes (11hrs). It starts watering at 5PM which seems like a really bad idea. It’s 7PM right now and it’s still watering… my phone alert said “will run for 307 minutes”. That’s obviously not 682 minutes. I’m just very confused.

I’d like to let the Rachio run itself, assuming it’s smarter than me about this. But this seems like an extreme amount of time to run, and watering prior to sunset seems wasteful too. Any advice?

Side note - my pressure can easily run 2+ zones at once but I don’t think the Rachio is capable of doing that… please, please correct me if I’m wrong.

@QFT Is this your first run use Flex Daily? How many zones do you have?

I just started the schedule - it’s run for about 3 days now. 7 zones.

@QFT The .4 inches per hour plus cycle and soak would lead to a very long watering duration.

Thanks, what is your suggested solution? Bump up to the default 1.0 IPH? Or would that leave me under watered? Change it to “Start after sunset?”

I’ll also mention that as smart as this thing is, not being able to water 2 zones at once is ridiculous… my dumb controllers could do that just fine, and it would completely solve this issue.

“End by sunrise” takes the total run time of all thr zones in that schedule and backs that off of “sunrise”. Even if not all the zones are set to run, it will start as if they were.

I have Hunter MP Rotators and they have a low precipitation rate too. Hunter says .45"/hr, but with a catch cup test, I’m more like .62"/hr. Not sure what grass you have, but here in AZ healthy bermuda needs 1" of water per watering every 3-5 days, so my system runs for 1h50m per zone.

As for running two zones, if you aren’t running a mast valve in the system, you can wire two zones together without any issue…


I’m in Colorado with a Kentucky Bluegrass mix on clay-filled soil. The Internet says it’s pretty thirsty grass. I have the Rachio set to “cool season grass”.

I’ll set my heads to .6"/hr which should cut down time by a third. And wiring two zones together might be a good solution! Thank you.

End before sunrise scheduling sets the start time assuming all zones will water each time it runs, which does not happen very often with flex daily. I would wait until Rachio calculates the start time each day depending on which zones are watering before bothering with this option.

Don’t change the precip rate setting unless you know what rate your nozzles are actually putting out . This would reduce run time, but Rachio will think you are putting more water down than you really are. Your zones will dry out before Rachio wants to water them again.

I suggest start by trying a different scheduling option (e.g. start at 2 AM, or after sunset if that is OK).

I think you want to try to avoid having all zones need to water on the same day.

You can schedule a few extra waterings manually so all your zones don’t have the same moisture level, and water on different days. If you aren’t watering all zones each day, then run times will be less than the maximum.

Another option is to split your zones, and set up 2 flex daily schedules that run on alternate days. That would cut the max run time in half.


I think you’re better off setting it to what the heads are supposed to put out unless you are up for a catch cup test.

Also, what do you have root depth set at, and is the grass well established?

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Thanks, you guys are great.

Grass depth is set to default 6" (I haven’t actually measured), and it’s a well established yard. And I’m setting my heads back to .45"/hr.

Looking at the future schedule, it must have been in its soak period because it’s no longer going to water every zone every night, which is great.

But… even though I’ve set it to “end before sunrise” it says it will water from about 5:30-8PM most nights, no additional runs. Why wouldn’t it wait until the early morning? That doesn’t make sense to me. Is that intentional?

Yes, again, Rachio takes the total run time for all the zones in that schedule and backs it off of sunrise. If it only plans to water 3 of the zones in a night, it is still hard coded to start at that same time as if all zone were running. Ideal? No, probably not, and I’m sure Rachio is working on those algorithms to fix that.


@theflexdude loses sleep over this. When he has time he wants to make this more efficient :wink:



Also at play here is also the fact that the Rachio starts off assuming that all of your zones are completely depleted (zero water reserve).

So your first run likely will over water by a LOT. I’d suggest manually “filling” all the zones since the only options are fill/empty for a more reasonable starting point.

IMO it would be very nice if they started off assuming that each zone is at the max depletion value, instead of 0%.

Or they could ask you how wet your zones are, although many people would probably not really know.

I was lucky, I set my controller to water using the same old school fixed schedules other controllers use when I first got it because I did not understand Flex Daily, and two days after I installed my Rachio got 3.23 inches of rain, the next day 0.83 inches of rain, and the day after that got 2.25 inches of rain. No matter how much ran off, this completely filled and saturated my landscape, so when I started understanding (just a little, still working to understand better) Flex Daily, everything was at 110%.

Actually, Flex will not change the duration of the run time at all whether fully depleted or not (assuming no zone changes were made). What it will do is run the schedule two days in a row to fill it…

I was experiencing something similar, I split my schedule in to two and used the interval days (odd/even) for each to split up the schedules (no watering restrictions). This effectively halved the max watering time so the ‘by sunrise’ start time became much later (earlier in the morning). Good luck.

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Do a catch can test. I bet your actual conditions are way off from the head specs. It depends on so many factors. Overlap, degrees, water pressure, etc. Only way to get an accurate accounting is to do the catch can test.

@theflexdude loses sleep over this. When he has time he wants to make this more efficient :wink:

My +1 vote for this. I think it is important to not start watering 9 PM at night because of the rot and other diseases that moisture on the blades can cause. Before starting, it obviously knows how much it’s going to run so we can take that subtract from sunrise and start later :slight_smile:. I currently have 2 flex-daily schedules and 50/50 zones in them running on alternate days to get around this but I read here and there that it may not be the best way.

I did this a couple of months ago and then it rained and everything was 100% and then everything went down to 0% around the same time. So, you would have to keep doing it every time it rains so may not be the best approach considering this is a set and forget system :slightly_frowning_face:

I understand. We don’t get many heavy rains during our watering season, so rarely see all zones filled to 100%. Most zones only water about once a week, so for me, unusual to have more than 2 zones water each day.

Maybe an alternative to Rachio fixing end before sunrise, is to add an ‘early start time’ parameter so that watering will not start earlier than that time, but stop at sunrise, even if all watering is not complete. The watering time for each zone could be prorated so each zone gets the water needed to make it to the next scheduling, some zones would get filled so not all zones need water next time.