Drip Emitter Calculator for Precipitation Rate & Area

I keep my grass MAD at 50%, but for my flower beds that are a mix of annuals and perennials I set the MAD to 25% – read that somewhere in some research out on the web (can’t remember now) and used it last year. Seemed to do well. You might want to do this for the drip zone for your liles.

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Do you happen to do the same for your garden @Linn, assuming that you have one ?

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I only have an herb garden, but I do the same for it.

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@azdavidr, I appreciate all your help on this. I’m currently in AZ and new to Rachio. My landscaper set up one of my zones to include both trees and shrubs (all on 2 gph emitters) but trees with more emitters, and shrubs with less. I was wondering how to go about using your spreadsheet you included with mixed zones? I was hoping I could just add up all my Emitters # of GPH (like 50 total [25x2gph]) to make it simple??

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@rsg You can treat them like they’re all on the same zone for the sake of the calculation, and you can set the run time and get a decent number to put in for the area. The area value will lead to more accurate water usage estimates but doesn’t impact your schedule.

What’s more concerning is the impact on your shrubs and trees on being on the same zone and therefore schedule. If you work through the Water Use It Wisely site, you’ll see that the watering needs of shrubs and trees can be quite different, but with your system you can’t give each of them what they need. You have to pick one or both (trees and shrubs) to be optimized, and the other will suffer. You can try to find a middle ground, but at that point both will suffer to some degree. I’d suggest when you can afford the time to have someone install a separate valve with irrigation lines to your trees. I say that assuming that you have fewer trees so it will be less expensive than adding a shrub-only line.

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So I’m brand new to Rachio, and have a gen 2 with one zone. The nozzles are what I’d call drip…but each dripper has like 6 little streams coming out in a circular fashion. Think of a grape, then have 6 low pressure streams of water. I’m completely baffled how to configure this in the app. I did the soil type research and got that input. I also tried the Rachio custom nozzle calculator but those numbers didn’t make sense. I ran my system for 15 minutes and according to my water meter it used 5 gallons. That came out to 34 inches and hour, but that’s vastly different than any nozzle spec in the app. Do I divide by the number of nozzles?

While I certainly appreciate the visual appearance of the spreadsheet, I haven’t the vaguest notion how to use it. First, I don’t know what plants I have. A landscaper installed them and all I know is they are drought tolerant (San Diego) and there are some knee high grasses, plus some other knee high stuff I have no idea what they are.

The whole thing seems highly confusing…I don’t understand how any homeowner can figure out drip systems. I mean the app doesn’t ask how many drippers you have. I just don’t see how you possibly get anything remotely accurate.

Any help is appreciated.

Are the heads something like this ?

Also, what are you irrigating with those types of heads ?


That’s what I was thinking too, those things can fill up my pool in no time when fully opened up

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This is by far the most useful thread related to drip irrigation setup on the Rachio. My wish is for azdavidr’s spreadsheet to someone be integrated into Rachio’s advanced settings.


Thanks @DroughtSaver !

Hey @azdavidr!

Lo with Rachio Support here! We LOVE this calculator that you’ve created and are considering linking it in a support doc. Could we have your permission to link it if we decide to go that direction?

Lo :rachio:

Sure, no problem Lo!


Thanks a bunch! We’ll report back if/when it gets published.

Have a great rest of the day :slight_smile:


I hope this isn’t too basic, but I just installed my Rachio 3 and tried to use your spreadsheet to set my daily flex schedules. However, there isn’t any information yet to determine the “inches of water.” Everything is a “0”.

Is your schedule on Flex Daily? If so, it should sure inches-of-water in the moisture tables. Sorry for the delayed response!

Wish this post could be pinned somewhere! I was just doing my annual review of my Flex settings and thought, “this is the post I ALWAYS come back to.” Thanks so much @azdavidr for your work on this and your tutorials (especially available water content).


You’re quite welcome, I’m really glad that you found it all helpful. Thanks for the post !

Pinned it to the Set Up & Edit Zones category :slight_smile:


We can pin? :exploding_head: