Soil type (according to the USGS data): BkC - Bingham Extremely Rocky Loam.
I don’t disagree. It’s more like boulders with a side of dirt.
Any given probe with a standard digging shovel has about a 60% chance of hitting a rock
Routing the sprinkler lines was a nightmare
Large rocks everywhere, as the development was put on top of a quarry.
Did I mention rocks? Rock on.
Level ground
Grass: A TWSC water conservation bluegrass cultivar that uses 30-40% less water than the stuff I replaced.
Soil Available Water Capacity (per the USGS) 0.11 cm/cm - I set this in the “advanced” settings for my zones, but I also have the soil type set to ‘Sandy Loam’ from a wild guess as the rocks don’t hold water to any extent.
I don’t know which takes priority, but I figure I better tell you my settings.
Sprinkler Rate: (Orbit Saturn III Rotary heads) - 0.3 inches per hour, per manufacturer.
I recently had new sod installed, so I measured the water rate to make sure I didn’t over/underwater in the sod. My measurement seems close to the rotary head’s spec.
Crop Coefficient: 50%
Root Depth: Just watered-in sod, but the previous lawn (same land) had 6” deep if that.
I’ve also used the ‘Map’ feature in Rachio, filled in the map for my zones, sprinkler head locations, and where they cover
Temperatures: 90-100 ℉ during the summer
Humidity: generally between 15-20%.
I’ve had the Rachio for quite a while -
I’ve wanted to be able to do the “Flex Daily” schedule, because what’s the point if the only thing I do is a braindead timer? Well, braindead appears to be the only thing that wouldn’t drown my lawn.
Braindead Schedule that “works”:
40 minutes per zone every two days.
I’m trying out cutting it back to 40 minutes every three, and so far, I’m wondering if I’ve been too conservative and should cut it back further.
Anyway: When I have all of the lawn/soil/sprinklers/map fed into Rachio (and lowering the crop coefficient to 50% compared to its default), Rachio wants to water: nearly 3 hours per station every day. . That works out to about 13.5x what is already too much water.
For fun, I tried changing the soil type to “clay” with the water capacity to 1.1, and it schedules 2 hours per zone every three days. Better, but I want a lawn, not a swamp.
I’d love to be able to use the “flex daily” smart schedule of Rachio, but I don’t live on the planet the Flex Schedule thinks I am on.
Does anybody have a suggestion on how I can actually get a ‘smart’ flexible watering schedule that won’t turn my lawn into a reflecting pool? (instead of just using a timer - at which point, why did I bother getting a Rachio?)
I truly believe flex daily is what sets rachio apart from other controllers. Especially when paired with the tempest. Unmatched when it’s set right. Also their API makes them stand out.
Other than that (The gloves are off, only a critique, lived a life never to kiss behinds), I feel it is an over price featureless junk box if you use it for “dumb” features. I prefer opensprinkler at that point and/or many others.
So I agree on the statement, “instead of just using a timer - at which point, why did I bother getting a Rachio?”.
–My recommendations–
In terms of the pooling. You are definitely going to need to know what the soil texture is and/or you are going to have to just experiment with what works. In Cali, we have Alluvial Soil Labs if you cannot find some university extension that would do it for you. USGS may not accurately get your pin point location’s texture and may not factor in what happened during development.
Always do a catch cup test across the zone and seem like you already did. Just pay attention which areas get more and which get less and factor that for your calculation.
Calculate the run time yourself just make sure the zone settings are set right but I recommend setting the efficiency to 100% so that Et calculations they do on their end don’t give weird values. I typically use (Amount you want to Water) X 60 / (Nozzle Precipitation Rate). So if you want to water 1/2 inch at a time (water not soil depth) as an example, and you have 0.3 nozzle rate then it is 0.5x60/0.3 = 100 (This gives minutes, yes 1/2in would require 100minutes or 1hr 40 mins). If you want to get the seconds just multiply the decimal of the minutes by 60 (Like 2.35 minutes or 0.35x60 =21 seconds or 2min21secs).
Again you need to know soil texture to see if you may need to cycle soak your zone or you may have to experiment on when pooling occurs and use that as your cycle time give or take and add some soak time like 30min to hr. Rachio software, in my opinion, can be very aggressive with their auto cycle soak depending on soil type.
I can’t disagree - development usually bring in truckloads of topsoil. I’ve got a neighbor that grew up here before the development was built - it was a quarry that separated the rocks from the rest. The rocks stayed, and the clay/sand/gravel was sold.
Having just ripped out the old (non desert-adapted) lawn - and then spent months tilling, leveling, and prepping the soil, I’ve spent a quite a bit of time working over every square inch. I’ll have to do a soil jar test this weekend… I certainly have piles of it laying about.
Nowhere in your criticism do you note that you’ve actual put a Flex Daily schedule into effect (ie: let it run) for any areas. If you’ve not used flex daily before, and you specify you have a large porous irrigation field (a large space for water through the depth of your profile), Rachio may be assuming it needs to fill that reservoir. And just because it proposes an unusual amount of water on the first day you’ve provided as available, doesn’t mean it’s done ANY calculation for what it will have to do the next day. The goal is to maintain a reservoir of water in the profile to avoid wilting the vegetation but not overwatering. You can drive grass roots deeper than 6”, and if you and Rachio succeed in doing that, you’ll water much more infrequently than you’re fearing. Deep watering, rarely, wasting none from the sky… that’s the ticket.
I can’t drive a pickaxe 6” deep. My house (and yard) are built on top of an ex-quarry. I just spend the weekend digging out the first 5” of topsoil over an area to put down a concrete pad. I had a layer of basketball-sized rocks, down to fist-sized rocks with a clay/loam dirt mixed in-between. I’m quite aware roots are great at finding every crack possible, but there’s only so much blood they can squeeze from the (literal) stone.
I’ve had the yard for 15+ years, and the Rachio for probably 6-7 years. Watering deeply is exactly what I’m accustomed to doing. I’m not there yet, and it’ll be a few weeks more at best (5 week old sod).
I’ve had years to set the Rachio on flex daily schedule, trying different settings. Each time, I’ve given it months at a stretch. It’s almost universally been an awful experience - both for the lawn and my water bill. We start to see root rot and visible mold problems on the grass because Rachio’s flex daily overwaters so ridiculously much, for months on end.
I’ve had freaking vigilante neighbors turn off my entire sprinkler system (the main ball valve is at the end of a 5’ pipe) because they didn’t approve of how much the Rachio is watering.
You have no idea how much I wish I was exaggerating. I’m here because I’m kind of at my wit’s end because the schedule it follows is just unhinged.
The method I proposed may help for the meantime (minus what is going on with rocks). I believe their algorithm (rachio) is buggy. The reason I said to put the efficiency to 100%, not sure how it works, but I guess in accounts for things like wind drift and other mysteries. If you did the catch cup then that is your 100% efficiency. You then go in, if your zone settings are acceptable like depth, Allow depletion, and available water. Because those 3 with DxADxAW will give you desired water amount. For example clay at 6.67 depth (D), 50% Allowed Depletion (AD), 0.15 Available Water (AW) will give you 0.5 in to maintain. Want a formula for what ever Desire Water Amount (DWA) you need and not sure the root depth. Use this (DWA) / (AD x AW). The parenthesis on the bottom is important. So plug what ever you want and divide it by (AD x AW) and you will get the root depth (again that parenthesis is important). Then hard code the time you want into the schedule (Use the formula from previous post). The reason, you bypass whatever bug is in the system. The only other bug that interferes with it that I know of is the water hammer bug.
Its my understanding that the questions about soils and whatever is the “basic mode” for Rachio just sets the “advanced settings” for you. And I didn’t find those to be particularly accurate.
You’re now at the point of needing to use the advanced settings and forget about the basic ones.
The reason your watering is so long is because Rachio is trying to fill a large volume of water. Imagine your soil is a cylinder with a circular area of 1square inch. You set the height of the cylinder at 6"inches. You set the soil capacity at whatever (the density the water will fill the cylinder). Your head is .3in/hr. Theres also an efficiency, which is how much of that .3 makes it into the cylinder. Then its basic math of how much time does .3*efficiency take to fill that cylinder…its a LONG time.
So reduce those numbers until it calculates to what you empirically know to be true. First set the efficiency to 100%– its just noise in my opinion, unless you have really bad spray patterns. Then reduce the root depth to 3”, or the available water to less. Those 2 equate to how much water the cylinder takes to fill up.
Then crop coeff is how much water evaporates (higher number for sunnier areas basically). You set that by waiting on the soil to dry in the sun. If the soil is drier after a few days than your system claims, then move coeff up.
And then the one that messes everything up, makes it so confusing, is “allowed depletion” This is how dry you want to allow the soil to be before you water it. The issue is, when you set it to say 60%, then it will water when calculated to 60% of saturated soil. But then your soil moisture displayed on a zone is of that 40% working moisture range. So 50% “soil moisture” is actually 80% of saturated soil ((100-60%) * 50%). This variable is really nice for some things like…if you just put seed down, crank that baby to 95% and it’ll water a little bit every day. Or put it really low and let you grass dry more and likely utilize more rain and less watering (less green grass though)
This post from RPostWVU is really good advice and so are the others.
I benefited from asking AI about which variables control what. For example, I needed to water more frequently and was directed to Allowed Depletion which I’ve lowered to .35 and did the trick.
You might want to review the Soil Moisture function. If you go to the zone and hit Soil Moisture you’ll be given the option to fill your soil (virtually). That should drastically reduce watering time. I’m assuming your Soil Moisture value currently is zero or thereabouts. I did not have a 13.5x effect, but I freaked out at the start over watering times. It has resolved after a couple of months. For certain zones I virtually emptied them and just accepted my fate that long watering was needed to fill up. Maybe you make some changes in soil and depth to drop the 13.5 to something less scary and watch the system react
Annoyingly, certain setting changes take some time (maybe overnight) to take full effect. I’d like to understand that better.
I think the system works; it just requires effort (time) to understand the sensitivities of the variables and iterations to tailor to your landscape. My St Augustine hasn’t looked better in 30 years.
. That works out to about 13.5x what is already too much water.