Setting Up Flex Daily in PHX with Mixed Plant Type

I live in the Phoenix area and got the Rachio 3 at the beginning of December. My old Irritrol controller died last year and got the Rachio 3 upgrade. I upgraded, mainly for the drip. The frequency was based on Moon Valley Nursery’s recommendations and the run times were mostly a guestimate. I think I wasted so much water from the drip and got the Rachio to save a lot of water.

1: Front Yard Drip
2: Back Yard Drip
3: Front Yard Pots
4: Back Yard Pots
5-6: Front Yard Lawn
7-9: Back Yard Lawn

I use Flex Daily Schedule for my drip (Valves 1-2). All the trees, shrubs, groundcovers, and vines are in one zone. The majority are under 20 feet so I use the shrub setting to keep the majority of the plants happy.

It last ran on December 2nd. I got 0.6 inches of rain in the middle of December. It is scheduled to water again on 1/14 or so. I am very surprised it has not run since December 2nd. The Rachio 3 currently has the run times at 3h 21m for each zone (1 and 2). I looked up my soil and it says Gilman Loams, which is 2in/ft or 0.17in/in. The watering time changes to 2h 50m for each zone and there are 2 zones on the schedule. at the new Available Water setting from switch soil types. The drip emitters are a mix of 1GPH 2GPH and 4GPH. Most of the emitters are 2GPH.

My current setup for Valves 1-2:
Zone Type: Shrubs
Spray Head: Emitter
Soil Type: Clay Loam
Exposure: Lots of Sun
Slope: Steep

Available Water: 0.2in/in
Root Depth: 15.8in
Allowed Depletion 50%
Efficiency 90%
Crop Coefficient 70%
Nozzle Inches Per Hour: 0.5in

Is there anything that I am doing incorrectly with the scedule?

I also use the Fixed Schedule for the lawn as I wrote down all the run times and frequency that worked for each month based on when the grass started showing signs of thirst for the past 3 years.

I also have above-ground 24 in diameter pots that I want to use Flex Daily (Valves 3-4). The pots might need a lot more fine-tuning than the drip.

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Looks like you are well on your way! You are on the right track with the zone type. Since you have a mixture of vegetation, you kind of need to error on the side of the most needy. It won’t be the most ideal watering for the larger trees, but it is what it is.

In looking at the soil type, I’m not familiar with Gilman Loam, but a Google search calls it a “course loam” as part of an alluvial fan. To me, I’d read that as a sandy loam?

I personally like to play with root depth to make adjustments, because in my tiny brain, I can visually see how it changes things. The deeper the roots, the less frequent it will water, but it waters for more time to get that water down deep to the roots. Just the opposite for shallow roots. How established are your plants, and what was your watering schedule prior? If you watered the plants multiple times a week for an hour, your roots didn’t have much incentive to dig deep, so you might want to adjust them up a bit. This will increase the frequency of watering. This is the biggest mistake people make (in my opinion) switching to Rachio. If you watered incorrectly with your old controller, you need to re-teach your plants, and this can take months.

Last item I would look at is your nozzle inches per hour. .5 seems a bit high. I suggest taking a look at this thread, and crunch some numbers in the calculator that @azdavidr created. Works wonderfully!

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Thank you so much for your quick response.

This is my soil type from UofA:

They say Gilman Loams are 2in/ft which is 0.17in/in, the same as Rachio’s loam setting. I think the water holding capacity is the same thing as Rachio’s available water. It’s good that my soil’s availability does not vary with depth.

I was following Moon Valley’s chart:

I was watering ONCE a week in the winter. TWICE a week in the spring and fall and THREE times a week in the summer. The duration was incorrect, which is why I was probably wasting a lot of water. I’ve only had Rachio in the coldest time of year. What is the frequency and duration of your waterings with your drip in the spring, summer, and fall?

The 0.5in/h figure came from Rachio and is in line with over 2GPH emitters. Most of my trees have several emitters and there are shrubs underneath the trees that share the water and extra emitters. Water Use it Wiseley said plants could share the water from the emitters.

I think that my drip has high pressure too so it’s wise to error on a high flow rate.

You can see my root depth setting falls in the range for the groundcover/vines, shrubs, and just short of the recommendation for the trees. I errored on the high end of the crop coefficient to satisfy the needy plants.

Most of my plants are several years old. I hand water some of the newer unestablished plants extra water between Rachio waterings. I have been keeping a close eye on all the plants, and they don’t seem to be wilting yet. It’s hard to tell this time of year though because I have several deciduous plants.

A large majority of the drip emitters on the market are pressure compensating, so its possible your pressure is fine. That being said, all drip should have a pressure reducer on it, otherwise you will blow apart emitters left and right.

I still think the .5 is a bit high. I have 4-6 2gph emitters on most of my trees and mine is set to .6, where my shrubs have a single and set to .35. Again, since you have a mix, you need might need to error towards shrubs.

The top of an emitter on the 1/4in tubing blows off ever month or so. The emitters emit a stream a water instead of a drip separated by air between drops.

The mixed vegetation is challenging. The run time must be the same because they are stuck on the same zone. I have 4gph emitters for bigger plants 2gph for medium plants and 1gph for small plants. The thought is to not let water go well below the root zone of the smaller plants by having a lower flow rate for the same run time.

How many emitters should I have for each plant? I want to prevent over watering some plants and under watering others.

You don’t NEED to have more than one, especially for small plants. All my shrubs (on their own zone) have a single 2gph emitter, and that will saturate the root area of the plant just fine with the 3h50m run time for that zone. For trees, I will have multiple depending on the canopy size. I still keep mine with 2gph emitters, but a small tree might have 2-3, and a VERY large tree might have 6-8 spread around under the canopy.

If you have emitters blowing off, it could be the tubing is just worn. Try cutting back to “fresh” tubing and re-install the emitter.

I changed the precipitation rate to 0.4in Per Hour as the majority of the drip is 2GPH. I will be swapping the non pressure compensating emitters to pressure compensating emitters too.

Rachio is now scheduled for 3 hr and 33 min for each drip zone on January 16th. The next day looks like the February 1st or so based on the weather conditions to reach 50% Allowed Depletion with a Crop Coefficient of 70%. The plants don’t seem to be complaining so far.

I only have multiple emitters for trees. Each shrub only gets 1 emitter. I use 1GPH emitters for small shrubs. Normal shrubs have a 2GPH emitter. I have at least 2 emitters per tree, with larger trees getting 3+ emitters. Some are 2GPH emitters and some are 4GPH depending how the tree size and how thirsty it is.

How often does your drip run for shrubs and what are your run times in Phoenix throughout the year? I want to know what to expect this upcoming year, especially in the summertime.

I replace the emitters and tubing as they break.

Shrubs run for 3h50m, right now last run 12/24, scheduled to run 1/14. In the summer shrubs will run about every 4-5 days.

Trees run for 4h20m, right now last run 12/24, scheduled to run 1/23. In the summer trees will run evert 7-10 days.

Winter is easy as the plants really don’t need much. Keep an eye in the summer as you may need to bump the frequency as the plant re-learn and push their roots deeper.

Thank you so much for all your help. It seems like my scheduled frequency and runtimes are close to yours.

I don’t think it will be too big of an adjustment for the plants going from 3 hour run times to 3h 33m run times while watering around 1/2 to 1/3 as frequent as I did with the dumb controller depending on the time of year.

Yes and no…the frequency is going to be what might make the plants suffer. The plants were used to getting water very frequently, so the roots had no need to go deep to search for water.

You predicted my summer watering frequency.

My flex daily runs approximately every 5 days on the combined shrub and tree drip. It wasn’t too hard of an adjustment for my plants even for the hottest June ever. I’m surprised they adapted to the flex schedule since I had got the Rachio 3 in December 2020.

My plants are happier than ever with the lowest June water bill yet!


What are your settings for your tree/shrub drip zone?

I have the default shrub root depth and the default tree crop coefficient

I might back down the crop coefficient or increase the root depth next year, but I’m letting the plants adjust in the meantime. I’ve only had my Rachio 3 since December.

I can’t make the shrubs completely happy and the trees at the same time on the same zone

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You have spray type as emitter and slope as steep.
My understanding is that slope only affects the smart soak cycle. So with a steep slope, there will be longer soak times.

However, I thought I read that if you select emitter, the system will not do a smart soak. For a smart soak, something other than emitter must be selected. Is that correct or not?

I have drip emitters that are 1gph 2gph and 4gph for the shrubs and trees. I selected steep as a few areas are steep even though it doesn’t cycle and soak. I probably don’t even need it anyways with the low flow.

If you have the spray head set as any type of “Drip”, cycle and soak is not used.

Yes, I did see that. I don’t need cycle and soak for the tree/shrub zones. I have it that way for the exact inputs

Why is the soil moisture capped at 110%? Is there a reason why it isn’t capped at a higher or lower value?

While I agree that it could be slightly higher (it used to be 120% LONG ago), I believe the thought behind that is that there is only so much water that will stay in the root zone regardless of whether it is 1" of water, or 6" of water. The same 1" will percolate through the soil at the same rate as 6".

I can kind of follow this idea when I flood irrigate my property. My front lawn areas will fill with 6-8" of water with 1 hour of flood irrigation run time. That water will percolate through the soil within 24 hours. Within a few days, the ground is “dry” again.