Flex Monthly - Guidance on Adjusting Intelligently


#1

Hi all,

I’ve had my Rachio Gen 2 for about 3 weeks now and I’m finally beginning to understand some of the smarts, but now I’m looking for guidance on tuning. I’ve gone through and very accurately categorized each zone per the 4 criteria Rachio asks for, though unfortunately, many of my zones have a mix of perennials, bushes and trees. Then I let the Rachio Flex algorithms do their thing based on the first round of info, leading to as schedule that watered most of the zones for about 50min every 6-8 days for the month of June. After the first watering, it was really clear that that approach was pumping out far water than the ground could accommodate - water was pooling and flowing to the street. I have since reduced the the runoff to almost nothing by manually reducing the runtimes by about 4x, but I’m sure that I’m not watering frequently enough now that I have gone somewhat manual.

  • We have about 6" of sandy loam with bay mud (similar to clay) underneath, plus a drainage system, that vectors extra water to the street, to prevent pooling on top of the clay. In a few places we have deeper loam but that’s in a raised bed where water buildup still likely quickly flows down to the clay. I don’t think my soil is behaving like the sponge Rachis expects.

  • I also haven’t had a chance to do a “can test” to see how much water I’m delivering. I plan to hoop up a flow sensor in a month or so, but I think I’m delivering more than Rachio believes I am.

Given both of those considerations, I would like to give another shot at generating a Flex Monthly schedule that is better adjusted for my real water and soil situation. Any pointers on what I should alter to steer toward more frequent, but shorter watering times. Do I change soil type, sprinkler head, or mess with the more advanced parameters ?

Again, I think I have to reduce most of my watering times by about 4x from the Flex Monthly calculation to avoid runoff.


#2

Root depth, soil settings and MAD. Take a look at this article for the details. There’s a handy table about midway down. It sounds like you have a decent handle on your soil, but if you haven’t already set your ‘Available Water’ consider doing that. Next up double check the root depth numbers. Finally, for things like vegetable gardens some recommend changing MAD levels, but I would research that for whatever you’re growing. I know that @Linn has run into some recommendation for adjusting MAD to less than 50%.


#3

Thanks for the pointer David ! Based on the short read and the outcome I think will be correct, I did two things:

  • Set zone root depth numbers for the shortest type of plant in each zone (usually perennials).
  • Changed the soil type in each zone from Loam (0.17) to Loamy Sand (0.07). I also looked up the USGS AWC for my yard and see that is estimated at 0.15 for the first 30 inches. I think my drainage system and other changes to avoid water pooling have reduced that number.

The result was a watering schedule that makes much more sense - more frequent, but shorter watering session, reflecting the lowered soil capacity. I still may do some manual adjustments to compensate for greater water delivery than Rachio estimates. Hopefully that will be more automated once I get a flowmeter installed.


#4

@KevBo Keep us updated on how your system performs after these changes!