Season Shift questions

(I also posted this on my original topic, but since it was marked as solved thought I should create a new topic. I did review the other threads suggested, but none of them addressed these two questions as far as I could tell.)

Mckynzee, thanks for the info, not sure what I was doing wrong but I can see the time changes now.

This does raise other questions though which are:

When I enter an initial time for a zone what does the seasonal shift assume that time to apply to, January or the start date of my schedule. For example, if I set up a schedule running from April to October and I set a starting time of 9 min., what I get is 12, 15, 15, 15, 15, 15, 12 for April through October.

What is the curve seasonal shift is using? Having the time curve go flat from May through September kind of ignores that June, July and August are much different that May and September. I’m trying to follow Denver Water’s suggestions for shifting times from May through October. Is the only way I can actually do that to manually change the times for all of my zones at the beginning of each month?


@davelr, just curious if you saw my reply to your questions (on the original topic)?

Your controller is currently on Standby so I cannot review the schedules, but happy to check the intervals if you’re okay with me taking the controller off Standby.

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Emil, sorry for the delay. Yes I did see your response and will include responses to your questions below. I should have mentioned that all I was doing at the time was turning season shift on for the fixed schedules that I had used last year.

To answer your questions:

@davelr, sounds like you’re applying custom durations to your zones? Rachio will recommend a duration based on the zone settings selected; curious if you’re overriding these values?

No, hadn’t altered anything. These were fixed schedules and I just input a starting time of 9 min. for April. I assume now that the season shift won’t really work correctly for a fixed schedule.

I’m not sure if you’ve reviewed this support article yet, but it details the math behind how the curve is calculated and applied. My assumption without looking at the data is that your base duration (9 minutes) is the root cause for the 15 minute max duration.

I had assumed that for a fixed schedule if I input a starting duration for April then the May duration would be adjusted by the curve, and so forth, whether or not this is the correct thing to do for the root depth. Obviously this isn’t what happens which is why I concluded that the season shift isn’t applicable for a fixed schedule. If I’m correct in that conclusion, I’d suggest altering the programs to not allow season shift to be applied to a fixed schedule to avoid confusion.

Remember to factor the intervals of the watering into your math. Your controller is currently on Standby so I cannot review the schedules, but happy to check the intervals if you’re okay with me taking the controller off Standby.

Given the above, I conclude here that the only way to properly apply an increased watering requirement curve to a fixed schedule would be to do it manually.

You’re certainly welcome to take the controller off of standby if you wish, I currently have the water valve closed, so no harm. However, I’ve deleted all of the fixed schedules from last year and turned on monthly flex schedules to see how they would work. This does result in situations where the weekly frequency of watering days exceeds those specified by Denver Water. I’m going to check with them to see if they have a problem with this or if they have some type of waiver for smart controllers. I know they have a rebate program for smart controllers, so this may be possible.

@davelr, I’ll review your schedules, but it sounds like we might be confusing schedule types and how they work.

On a Fixed schedule, If you alter the zone duration recommendation, your entire schedule going forward will update with the appropriate seasonal offset. In other words, Seasonal Shift will change your durations using your new duration time as a baseline. We make a relative change to the other months’ durations so that your watering schedule always matches the ET curve.

If you’re using a Flex Monthly schedule, the interval is the major variable that changes and minutes have a minor adjustment to account for rounding. Flex Monthly schedules apply Management Allowed Depletion principals to the entire schedule; whereas Flex Daily schedules apply Management Allowed Depletion principals on a zone by zone basis.

Relative to above, I believe we’re confusing schedule types and how seasonal shift works. Seasonal Shift is automatically enabled for Flex Monthly schedules and cannot be disabled. The feature can be disabled on Fixed schedules.

Seasonal Shift on Fixed schedules will change the watering duration to match the ET curve. On Flex Monthly schedules, the watering interval is changed on a monthly basis to match the ET curve.

Happy to review these recommendations from Denver water to your recommended schedules if you’d like to share or send them to us (

I’ll review your schedules in more detail to help clarify your Seasonal Shift questions.