# Smart controller questions



## MDJoe (Sep 16, 2019)

Due to my low yielding well, I can't irrigate all of my yard, but I can possibly do the front (10k) and my 1.5k veggie garden if I space out the timing.

What I wonder about are all of these "smart" irrigation controllers on the market. A lot of them say they can adjust watering based on past rainfall, and rain in the forecast. Which is where I go "wait..."

We have been VERY dry here in MD since early August. I can't tell you how many times rain was in the forecast, but we ended up getting a 0.02" sprinkle or less.

Are these controllers going to delay watering when you end up getting next to nothing, and your lawn therefor ends up brown anyway? How well do these things work?

Or, can you hook them up to your own weather and have them adjust based on actual rainfall received?

To me, a "smart" controller would say "well I'm supposed to come on today at 8 AM. I'm supposed to water 1 inch, but my rain gauge says we received 0.65 inches of rain this week, so I'm only going to water 0.35". Does that exist?


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## dhmeiser (Sep 18, 2019)

I was looking for a controller with a moisture sensor which is controlled by soil moisture. 
I saw this one https://spruceirrigation.com/

It is supposedly a smart irrigation controller which can link to multiple sensors 
I have no idea how well it works and this is relatively new, from a crowd-sourced start up company.

I have used smart moisture sensors before for flowers in pots and urns called plantlink, but Scott's purchased the company and shut down the internet connections and phone app. For this reason I am reluctant to purchase this system as typically with startup tech they go out of business or get purchased and their equipment becomes not supported by the new company.
Also professional soil moisture sensors are expensive $300+ for just the senor and added expense for the measuring unit and the sensor they have on their page looks like it is made out of PCB board and will not stand up over time.

there are DIY systems as well as seen on https://www.instructables.com if you are handy building and electronics.


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## hsvtoolfool (Jul 23, 2018)

MDJoe said:


> Are these controllers going to delay watering when you end up getting next to nothing, and your lawn therefor ends up brown anyway? How well do these things work?


"Smart" controllers don't use weather predictions, but daily conditions taken from local weather stations in your area. The values used to decide when irrigation is needed include daily rainfall (duh!), temperature, wind, humidity, barometric pressure, and so forth. These are all measured by local weather stations constantly broadcasting the data on the internet. There may be several weather stations in your neighborhood, or there may be only a few NOAA stations in your county. You can find the nearest available stations here...

www.wunderground.com

I haven't set up my Rainmachine yet...too lazy and too much other stuff on my plate.... but a quick glance at the "Wundermap" shows I've got 3 stations within 1/4" mile of my house. It's pretty cool, but frankly I'm shocked at how many weather nerds there are in my neighborhood. Given your location in central Maryland, I bet there are a bunch of stations near you...

https://www.wunderground.com/wundermap?lat=39.385794515093885&lon=-77.13020324707033&zoom=13

But if we suppose I had no internet in my area, or no weather stations near me, both the Rainmachine and the Rachio brands have open programming tools which allow me to install my own weather station in my back yard and then feed that data to my irrigation controller. In fact, I plan to do that someday just because it looks like a fun project. There are a few folks here on TLF already experimenting with personal weather stations.

Finally, I'm sure old-school irrigation controllers with soil moisture and rain sensors help to reduce over-watering, but I suspect folks are tired of replacing those sensors every year or two. Or perhaps Big Irrigation just can't design controller software sophisticated as Computer Nerds who build wireless devices. Regardless of the reason, "smart" controllers are gaining popularity over the old-school approach.


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## hsvtoolfool (Jul 23, 2018)

Sorry, I just finished and then saw you posted in the "Rachio Sensor" thread that pretty much answers all your questions. Doh!


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## Riverpilot (Mar 26, 2019)

Also look into the Hunter Hydrawise. This is my 3rd season with it... I also have a backyard weather monitor, that connects to wunderground.


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## jayhawk (Apr 18, 2017)

I have rachio- and mange the hydrawise for the HOA. Hydrawise doesn't consider spray head types (percip rate), slope, soil type, grass type today so you have to know how long to run first


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## g-man (Jun 15, 2017)

I have a rachio, but I know that opensprinkler has some nice options and open source community.


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