Seasonal Adjustment

Hi, I just got my first Seasonal Adjustment in the email today and noticed that the watering times was increased 8.5% or five minutes. The stats says that that it has gotten about 2 degrees cooler with no rain detected. I was thinking that with the shorter days and cooler temps that the watering times would have decreased but instead it increased. Can you educate me as to why it turned out the to be the opposite? BTW, the yard looks healthy and doesn’t seem to be struggling.

FYI, here is the email describing why it was adjusted:

Since your last adjustment, your seasonal temperature has changed from a range of 67-87°F to a range of 65-84°F, and the average daily rainfall has changed from 0.01 inches to 0 inches. These and other seasonal changes (length of day, windspeed, etc.) have increased your watering needs by 8.5%.

Your new total seasonal adjustment is 8.5% (0.0% + 8.5%). Previous week adjustment total was 0.0%. This seasonal total can be adjusted manually through the Rachio smartphone app on any watering time.

@rgarza28‌ We look at the median evapotranspiration since the last time we adjusted the schedule to the next time and take the percent change from the two. Other factors like solar radiation, wind, and humidity play a large part in the calculation. So, unfortunately just looking at the temperatures alone can be misleading. If you feel that you don’t need an adjustment you can always navigate to the watering time in the app and just move the adjustment dial.

We are always trying to refine the adjustment algorithm and are starting to look at modifications we can use to enhance adjustments and our rain delays.

Thanks and let us know if you have any more feedback or questions.

Oh ok. More variables are at play than when we normally think about. I’ll leave it as is for the time being and watch it for a month.

Thanks for the feedback.

I received notice of a watering adjustment in my email today. The email said the adjustment was -3 minutes (in the photograph area). Then, in the next section below, the email listed the actual adjustment as being from 15 minutes to 14 minutes, or 1 minute total, which it further said was about a 6% change.

So what explains this fuzzy math?

  1. Is it possible that -3 minute adjustment is actually an hourly figure, recalculated and rounded to list a 1 minute change for my 15 minute watering period?
  2. So then the statement of a 6% change was based on the 1 minute time change? Because 3 minutes out of 60 is, of course, a 5% change.

Maybe listing hours, minutes and seconds would be an alternative?

@eganders‌ I looked up your water budgeting. I see 6% off each zone (3 total). Old time was 15 minutes (900 seconds) and new time is -54 seconds (846 seconds total). So -54 seconds off of each zone for a total of -3 minutes (rounded). Does the email reflect differently?

Thanks and have a great day.

I am going to add to this post, because I also have questions on the Seasonal Adjustment. As you may know, Texas has been getting pounded by rain – the good thing about this is not having to turn on my sprinkler system! :slight_smile: However, I’ve received recent notifications that whenever I will need to water in the future, my watering schedule was adjusted by +18% to my current watering times.

To my question - with the almost foot of rain North Texas has experienced, beyond skipping watering the yard (which the Rachio does really well taking in data from my PWS/Netatmo station), shouldn’t it also be smart enough to almost override the logic behind Seasonal Water Adjustment looking at the last 2 weeks or 30 days of total rain + watering accumulation? i.e. not make adjustments or at this point, reduce the amount of time needed for each station to water?

Btw, I’ve manually gone in reset the seasonal adjustment back to 0%. :smile:

I’d like to add my two cents as well. Over the past 2-3 weeks, I have had seasonal adjustments each week. Each time, they adjustment has been to reduced watering times. However, we have had a long dry spell. The temperatures have been cool and I’ve been irrigating less often anyway. However, this week, our temperatures have climbed significantly (+ 20F). We are still dry.

I don’t understand why the watering durations have continued to be decreased.

Also, i still don’t understand what the baseline is for the decisions of watering durations for the seasonal adjustments. I assume it takes into consideration the configurable details, such as soil type, pitch, irrigation head type, plant material, etc. However, does it take into consideration the recent temperatures, actual precipitation in the past and present?

I have also been told many times that it is best to irrigate turf less frequently but for longer durations. This trains the turf roots to go deep looking for water which creates a better root system. Is longer watering times but less frequent considered? If I’m already only scheduling irrigation of turf 2-3 times a week and I’m watering longer, will the seasonal adjustment consider this, versus someone who might be watering daily for shorter durations?

Yes, that! This is flex schedules coming out soon, based on managed allowed depletion. We will automatically modify the frequency of watering for you, treating each zone like a checkbook (evapotranspiration = debit, precip + irrigation = credits)

The current incarnation of water budgeting works off of a rolling evapotranspiration (ET) trendline, looking backwards and forward and taking the week-to-week median of ET for your area.

It works well for most people, but IMHO flex schedules will be much more efficient. The one recommendation I would make is that at the beginning of the season if weather is changing drastically, it might be helpful to re-calibrate WB to zero every so often to offset a dramatic increase or decrease in temperature changes.

Hope this helps. :beers: