Rain Bird SMRT-Y Soil Moisture Sensor Kit

I don't get why these new fangled smart sprinkler controllers exist. They will use the current weather report and future weather to figure out if your garden needs to be watered. No need for any sensors! Am I seriously the only one who sees how stupid that is? Not only is the weather station probably miles and miles away from you (which makes the report inherently inaccurate), the forecast is still speculative at best. Also, how will it know how much water the soil actually has? Complex algorithms that calculate the amount of water gets spit out by the sprinkler heads, the amount of runoff, the amount of sun and humidity and temperature? Really? So basically, rather than it being smart, those systems rely on hopes and dreams. Yeah... not gonna work, buddy. Oh wait, they're on wifi, so you can control it on your phone, even if you're not at home. OK, that makes sense. That way, you can tell it what to do while you're on vacation when when these smart controllers will keep screwing up your lawn. Now here comes the soil moisture sensor kit. This is a WIRED device, so no need to change batteries every so often. This is truly set and forget. Just bury it somewhere in your yard, and the controller does the rest. It'll figure out your field capacity (water capacity for your soil), then it'll give you a recommended 80% threshold where when the moisture level is below 80%, it'll allow watering. Cool. You want it at 75% because of the type of grass you have? Sure. just program it as such. You have very clay-ey soil? No problem. It'll calibrate itself for it. Deep roots? Well, just bury it deeper. Did it just rain a lot, so you don't need watering anytime soon? Well, this little guy will know and will stop the watering schedule until the soil is dry enough that it needs more water. It's simple. Rather than relying on hopes and dreams, it relies on a simple device that asks, "how dry is the soil?" Can't beat that. This thing is pretty precise as well, with good resolution of measurements. I dare you to find a smart sprinkler system that can beat this guy.

I am on my 2nd SMRT-Y sensor - having to replace the original 5-year old sensor that failed a few months ago. For reference, my SMRT-Y sensor controls a 2-station irrigation controller connected to drip irrigation for my residential desert / xeriscape landscape in the Mojave Desert of Las Vegas. I have no idea how it will perform in an irrigated lawn environment. However, in a drip irrigation setting for my conditions, it has performed flawlessly. On the Plus Side: This sensor does exactly what it's supposed to do. For my desert plantings, I have it set for 13.0% and the sensor was buried 8" directly underneath a series of drip emitters. I have the controller set to water every day at 7:00am, and if the soil moisture is above 13.0%, then SMRT-Y will suspend the irrigation cycle. In the summer when daytime high temperatures are normally >105 deg, it will usually allow an irrigation cycle once every 2-3 days - which is perfect. In the cooler winter months, this sensor may only allow an irrigation cycle one every 2-3 weeks - also just about perfect! On the negative side: This sensor only seems to last about 4-7 years. When I dug up the old sensor, it looked brand new - there was zero corrosion or other visible reason for it to fail - it just did for some reason. The stainless steel rods on the old unit looked good as new. The only reason I can come up with for why it failed is the internal electronics. The buried electronics are totally sealed in epoxy resin, so there was no reason for a contamination-related failure. Basically, the electronics of the buried unit just gave out. As a DIY tip: Make sure you use top of line, good water-proof wire connectors when wiring this sensor up - don't skimp on that part. The SMRT-Y is not the easiest thing to get wired-up and going, but once it's working and your settings are dialed in? It's golden Would I recommend it? Yes, Absolutely - it does save a lot of water. Just realize you'll probably be replacing the buried sensor every 4-7 years. If you're good with that going into the project, then buy it. This sensor beats any weather station setup by far. It truly is a water "thermostat" in your yard.

It does what it is intended to do and does it well. Installation was simple and straightforward with good instructions.

UPDATE Jan 2019: I've been using this now for 2 years: 2 moderate/dry winters and 2 torid summers (Phoenix.) So far this has worked flawlessly. I haven't touched it in over a year-and-a-half. All I do is check my yard occasionally and watch my water usage cycle up and down as the seasons change. Very pleased! I've had this in the ground now for about 4 months. Working very well and as advertised. I live in the greater Phoenix area, so my conditions are different than most, but probably on the far extreme, so if it works for me, it will probably work for about anybody. As I don't have a lawn, I'm using it for shrubs and will install a second one for my tree line. For shrubs I buried it about 15" deep, because that's about in the center of the root zone. I chose a representative shrub as far as size, demand and evaporation rate. Since I knew that I needed to water about every 5 days at that time of year (late Summer) I calibrated it such that it would turn on at about that interval (12%). Amazingly, as the temperature cooled the interval started to increase. We have had some winter rains, so it hasn't watered in about 2 months (winter). Looks like it will water in about another week unless we get more rain. Plants look just fine...so that's pretty much the acid test. I'm going to install another sensor on my tree line. Will bury it at about 24 inches, since that is about mid-root zone. I have it connected to an Irratrol Rain Dial. My only concern is longevity. I have a concern that eventually roots my grow into the loop and break the device, but can't know that until it happens.

I bought a Rainbird SMRT-Y sensor and connected it to a Rainbird ST8x-wifi controller to handle the 6 zone sprinkler system for my lawn. I would like to run 2 zones each night resulting in 3 nights to complete my watering cycle. Unfortunately, one SMRT-y sensor will not work if you have 2 or more zones which you want to run over several nights. Consider the following example. You have 4 zones in your sprinkler system with one SMRT-y sensor in zone 1. You want to schedule zone 1 to run at 3:oo am and zone 2 to run at 5:00 am on the first night and on the second night you want zone 3 to run at 3:00 am and zone 4 to run at 5:00 am. If the SMRT-Y sensor changes to allow watering on the day zone 1 is scheduled zone 1 and 2 will run with no problem that night as scheduled. However, now that that zone 1 is wet the SMRT-y will not allow zones 3 and 4 to run the next night. Bottom line is you must run all your zones contiguosly to make one SMRT-Y work. In my case I would need to run all six zones in one night taking 12 hours non-stop to irrigate the entire lawn. This would result in watering durning the day which no-one recommends. You can solve this problem by adding another SMRT-Y to zone 3 and 4 to control them however, this gets expensive especially if you have 6 or 8 zones. So far I have had no luck getting Rainbird's call center people to understand the problem. Finally, SMRT-y sensor does not communicate it's status to Rainbirds ST8x wifi controller's phone app so you don't know if the sensor has cut watering off or not.