Struggling to get settings right for drip

Hi all…

Used Rachio for a while, but I never “trusted” the numbers coming off of the Rachio daily and just ended up changing them myself to a shorter time (I just found out that Rachio doesn’t work well when you change the length numbers on Flex Daily apparently-- doesn’t accommodate weather changes as well?) … as they were always way longer than seemed to make sense. Trying to put a little more work into it; but after reading the knowledgeable and forum, I’m more confused. Would love some help getting this right.

So, recently I’ve replaced everything with drip. It’s all perennials, annuals, vegetables or trees; no grass at all.

There are over 10 zones; and I’m having trouble getting anything consistent.

All the soil is formerly compacted clay but hard tilled this season with compost, and I’ve been giving it some love.

Common settings :

Area - I’ve not been careful about these. As these aren’t lawns, the area isn’t linear or easy to box.
Available Water - Did some lookups as noted on this site, came in at 0.16 in/in
Root depth / allowed depletion / efficiency / crop coefficient - as recommended for the category

Nozzle inches per hour - probably the most confusing one for me. Dripline and emitters come in at 0.5-0.6 in the auto setting. I’ve been assuming that since 1gph emitters over an hour put .6 inches of water into 1 soft, that was the baseline.

Zone 1 - probably the most confusing - Fruit trees. They’ve got 0.5gph/1gph/2gph drips on the trees and some drip line in the extents - in relative ratio-ish of the area of the canopy so that the EV ratio from them are similar to each other; so they can have the same timing. What nozzle inches do I use? Any other settings to change?

Zone 2 - Older large trees and hedges - The gardener set it up with drip line running in front of the tree drip line - 1 gph every 12 inches.

Zone 3 - Vegetables I have outside, with emitters and soaker house. Almost all the veggies have 1gph each, but tomatoes have 2x 1gph on each side.

All of them suggested really long water times and more water than I thought I’d want to put into the ground at any given time (for the veggies for instance, which suggest an inch of water on each fill ; so 1.6gal - but the timing suggested would put in almost three.

Any idea what I’m getting wrong? Should I really be putting in that much water in the ground at a time - or have I put emitters too large for the 0.6inch nozzle inches per hour; and I should be using something else?

I’ve been using allowed depletion and increasing it when the soil is overly dry and the rachio doesn’t catch it (to increase the speed). Not sure what to do with efficiency.



The best I can offer is this post if you haven’t seen it yet:

But I must admit even after reading it, I was still mostly confused. I’ve been trying to chase similar questions for the last week, but haven’t been making much progress really understanding how to combine drip with Rachio. I’m starting to get an impression that Rachio simply hasn’t been designed to work with drip irrigation. it’s primary (and maybe sole) use case is lawn irrigation as it assumes more or less uniform coverage.

A few days ago I started to to play around with some ideas using a zone with with a handful of young fruit trees (the only zone I have that is entirely drip and is made up of similar vegetation). I stumbled across a guide put out of the University of California, Davis on how to grow fruit trees (in CA) and it had a useful section on drip irrigation. The one take away for me was that when on low-flow drip emitters, trees should be watered daily. There is also a table of how much water trees need based on their size and a few other conditions.

So I set the zone’s efficiency to 100%, Available Water to 100%, and Allowed Depletion to 1% (to force daily watering). And now I’m just manually tweaking Nozzle Inch per Hour to get watering durations that will give me amounts of water that match the numbers in the table I mentioned above (I also have different number of emitters per tree to compensate for variation in tree sizes).

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I don’t think we should be watering daily, that’s not what I’ve seen in my research.

Would love if Rachio care could reply on what we should be doing, as “I’m starting to get an impression that Rachio simply hasn’t been designed to work with drip irrigation. it’s primary (and maybe sole) use case is lawn irrigation as it assumes more or less uniform coverage.” would concern me…

I’m in the north Phoenix area and my drip runs 3h 33 minutes per zone on flex daily. It’s a combination between trees and shrubs

Gilman Loams (0.17in/in)
AD 50%,
Crop Coefficient 75%,
Root depth 15.9”,
90% efficiency
Lots of Sun


once a month in December, January, February,
3 times in March,
~once a week in April,
~once every 6 days in May
~once every 5 in June

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@ECOBEARD: Unfortunately, by themselves these numbers don’t say much. Depending on whether you use 1gph or 4 gph emitters, 1, 2, 3, 4, etc. emitters per plant you could be applying anywhere from 3.5 to 56+ gal per plant per watering.

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@ rizzyk: A better way to put this is not that Rachio isn’t designed to work with drip, but that the application interface isn’t optimized for drip systems.

BTW, here’s a quote from the article wrt “daily irrigation”:

Soil type or depth has very little influence on drip irrigated trees since the water use rate is determined by weather and trees size. Soil water holding capacity is unimportant due to daily irrigations. Based on tree response from irrigation studies, it has been determined that for young trees it is beneficial to irrigate them by a factor of 2 (double) until the trees reach 70% full cover. It seems that “over irrigated” young trees grow even better than if they receive their daily water use allotment based on evapotranspiration.

I personally don’t agree with that article you posted from Cal, and have a number of articles I can share to the contrary. Unless you are talking very young trees, in which case, they could need almost daily watering in the hottest months due to the lack of a root system. I also don’t believe that drip irrigation is “designed” to water every day. If your drip irrigation puts down the required water for a plant and can leave the soil with reserves as the ET eats away at it, it doesn’t really matter how it is applied. I work with a number of large Ag farms, and not a single one of them waters daily whether it is flood irrigation, sprinklers, or subsurface drip. Crops range from roses, to vegetables, to fruit and nut trees.

The “issue” with the way Rachio handles drip is that no drip is measured in inches per hour. Everything is gallons per hour or gallons per minute. It take a small bit of calculation to figure out the inches per hour. Otherwise, the watering algorithms on the backend are the same regardless of irrigation type.

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Right that’s why I corrected myself saying that only the UI isn’t designed for drip, not Rachio itself. The fundamental concepts ET, soil capacity, etc. don’t change between drip and sprinklers.


@beranes Glad to see you say this. I’ve been staying out of the discussion because I got my drip system to work really well with Flex Daily. But I totally agree with you that it’s the UI (or maybe even better said that calculating the “inches/hour” that a drip system puts down can be difficult - just sooooo many variables). Once you figure something out, it actually works quite well.

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I will agree with that, but I hate to say that it wasn’t “designed” for drip, but I get what you are saying. I think at the end of the day, the programming algorithms for the schedules are calculated using inches per hour, and to change one particular irrigation type to gph is probably a monumental feat.

I sent a DM to @rizzyk but I’ll post a response here.

After reading through the thread, the issue is with understanding the Nozzle Inches Per Hour. @beranes linked an article earlier with the calculation to convert GPH inches/hr.

Washington State University has a free calculator online that you use (here) You just need to convert the gallons per hour to inches per hour and input that into the Advanced Zone Settings.

Also, check out your drip-line manufacturers website. Most of them have their own online calculators where you can select your drip-line model number for better accuracy. I have always liked Netafim’s calculator here. Netafim also has an Android and iOS app.

@dane, that calculator works well for drip tape or drip beds with even spacing, but for point type drip emitters, this won’t work.


I’ll echo what @tmcgahey said. I’ve seen most, if not all, popular online calculators, but they all assume that there is an area uniformly covered by drip emitters. Yes, when you have uniform coverage, converting from drip’s gph to lawn’s iph is quite easy because both systems are area-based. Most of us here asking drip questions struggle with making Rachio work with single point irrigation (drip or bubblers). Please take no offense @dane , but if anything your comment only further highlights the issue: this worldview of uniform coverage underpins Rachio’s entire interface design, making single point irrigation into a kind of a bastard child :slight_smile:

@tmcgahey and @beranes I appreciate the discussion and the feedback here. I’m highlighting this thread to our product team to research this further.

Please excuse my further ignorance on the matter, but would a catch cup test be the best way to determine precipitation rate for single point drip irrigation?

Also, are there any examples that you could DM me where this type of drip irrigation scheduling is done well?

@dane I personally don’t know what the correct answer is here. Being able to enter this field in gallons per hour as opposed to inches per hour would be ideal, but even if that is doable on the programing side, I’m not sure how to completely make it work in a mass scale. For instance, my tree zones all have 2 GPH emitters on them, but the number of emitters depends on the size of the tree. I have anywhere from 2 per tree to 10 per tree for my thirstiest trees. What would I enter as GPH? 4? 20? Somewhere in the middle at 12? I’d argue that this setup is a more ideal way to handle multiple sizes and varieties of trees, but many have the same single size emitter going to every tree. This scenario would make entering GPH easy, but arguably, something is either going to get too much water, or too little.

That is where I think people struggle with Rachio. They want it to be perfect out of the box, but it takes tweaking based on your yard. EVERY yard is different. EVERY irrigation system is set up different. To say that there is a setting that is going to work for everyone is a compete farce.

What I would prefer is to be able to tell Rachio to deliver a fixed amount of water per watering based on the smallest granularity I have available and then take care of multipliers myself.

Here’s what I mean by that. Let’s say I have a zone where the smallest amount of water that needs to be applied per watering based on the kind of plants I have is 1/4gal and the smallest emitter I want to use is 0.5gph. So that’s what I tell Rachio: I need 0.25gal using a 0.5pgh emitter. Rachio now schedules a 30 min run for this zone. (Frequency of watering is a whole other thing, but let’s assume that at least the zone is homogenous enough that all plants can be on the same frequency)

Now, knowing that Rachio will run the zone for 30 mins makes it easy to adjust irrigation of other plants based on their own needs. If I have a tree in the same zone that needs 10 gals per watering, I may put 5x4gph emitters on it.

All of the above can be easily done with a fixed schedule. The trick is bringing flexibility into it based on daily ET fluctuations. That’s where Rachio’s “magic” should kick in. I have no idea how to bring ET into this model of watering. It may not even be possible, but I’ll leave this to Rachio’s geniuses :slight_smile:

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I found this Univ of Cali study last night, might help with what you’re trying to do, at least to see what different ET fluctuations change estimated water per plant to.


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@beranes your idea make sense to me, but how many post do you see where people don’t even know what they currently have in their yard so they can enter into the current set up, and you want to have them add more emitters based on the additional watering needs of larger trees calculated off a base GPH setting of the smallest plant/emitter combo. At some point, Rachio needs to make this for the masses, not just lawn nerds like us. :joy:

@tmcgahey: Totally agree and that’s why I’ve been saying all along that Rachio’s UI isn’t set up for single point irrigation, which is a whole different paradigm. To be successful, an application’s UI (or to be technical UX - User eXperience) is normally created to fit a certain paradigm. So far, Rachio’s paradigm has been lawn irrigation and with it came certain choices for what to include on zone configuration screens and/or how to drive user interaction workflows. Adding proper support (as opposed to an afterthought that it is today) for single point irrigation would require redesigning some screens and workflows to make the entire User eXperience (UX) more intuitive.

For example, since tree size is very important in figuring out how much water needs to be applied, perhaps in this new paradigm the app would guide a user through the steps of specifying how many trees they have on a zone and their specific sizes/ages/types. Taking this further, maybe even making recommendations for how many emitters and of what flow capacity to install for each listed tree.

In fact, I think to be really effective the Rachio app needs to transform from an irrigation controller app into a garden/yard management app (I think inclusion of Yard Map in Rachio 3 is a step in that direction) where users can keep inventory of their plants, sprinklers as well as keep logs of changes, a schedule of required maintenance work, etc. Then data from the yard management part of it can be fed into AI models for improving irrigation effectiveness, i.e. water usage and money, thus improving Rachio’s own value proposition.