Keeping your lawn or garden properly watered with an in-ground sprinkler system requires a bit of work. You need to adhere to your local watering ordinances, program the system controller to prevent overwatering (or pay a pro to do it), and hope you’re around to shut off the system to save water—and money—if it starts raining.
The smart sprinkler controller aims to soothe those pain points. Just as smart thermostats have revolutionized the way homes are heated and cooled, automatically adjusting temperature based on your habits, a smart sprinkler controller adjusts watering depending on the weather. These electronically controlled devices, which cost $100 to $300, replace the existing programmable timer on your sprinkler system to open and shut the water valves. So instead of following a set schedule, your sprinkler can follow the forecast.
These devices don’t have gauges that record actual rainfall; instead, they have a WiFi connection that allows them to use weather data from the internet to determine watering schedules. If the controller knows that an afternoon storm will dump a ton of rain, it will delay watering that morning or perhaps even for several days depending on the amount of rain.
“These sprinkler controllers are nice for people who want to fine-tune the watering of their lawn and garden,” says Larry Ciufo, CR’s test engineer for sprinkler controllers. “But they can be intimidating at first due to complicated wiring and app controls.”
In CR’s tests of smart sprinkler systems, we evaluate how easy it is to wire the controller to the sprinkler system’s water valves, whether the controls are simple to use, and whether they’re weatherproof. We also track whether we ran into trouble connecting the controller to the internet. To gauge a system’s watering accuracy, we collect actual rainfall data from a rain gauge, and then evaluate how much a controller overwaters or underwaters based on that data.
Below are five key considerations to take into account if you’re thinking of installing a smart sprinkler controller, followed by the top-rated models from our tests. For more information on all of the controllers we test, see CR’s in-ground sprinkler controller ratings and buying guide.
1. WaterSense Certification Is a Must
Sprinkler controllers can carry the EPA’s WaterSense certification for watering efficiency and conservation, just as home appliances can carry the Energy Star certification for energy efficiency. In order to receive a WaterSense certification, sprinkler controllers must incorporate local weather data and landscape conditions into its watering schedule instead of simply functioning as an on/off timer.
According to the EPA, a WaterSense sprinkler controller can save the average U.S. home 7,600 gallons of water per year, enough water to fill a small swimming pool. That’s good for the environment and good for your wallet, too.
All of the systems we test carry a WaterSense certification, but that doesn’t mean they all have the same watering schedules. That’s due to differences in the weather reports each model uses. Our tests account for these differences. How accurate a controller’s watering schedule adjusts to the weather shows up in our weather responsiveness rating. “We found that some systems made more granular changes than others, thanks to more sophisticated sets of weather data,” says Ciufo.
To see which systems are most effective, check our complete ratings chart.
2. Know Your System’s Watering Zones
In-ground sprinkler systems are made up of multiple zones of tubing and sprinkler heads. The system then sends water to each zone one at a time, because homes usually don’t have enough water-flow capacity to supply all the zones at the same time. Controllers are sold based on the number of zones they can handle.
Most of the controllers we tested can handle seven or eight zones, and many offer variants that can handle more. For example, the eight-zone Rachio 3 sprinkler controller, $230, also comes in a 16-zone version for $50 more. Make sure to check the number of zones your system has before purchasing a new controller. If you buy a controller that doesn’t have enough zones, it won’t be able to water all the necessary areas.
3. Installation Involves Rewiring
If you’re not comfortable doing wiring of any sort, you’ll need to hire a professional to install your smart sprinkler controller. The wiring that’s involved is low-voltage, though—just like for doorbells—and you can install the device yourself using the manufacturer’s instructions as a guide. The process is similar to installing a thermostat to control an HVAC system. You simply insert the proper wiring into designated terminals.
4. Consider the Controls
Most of the models we test allow you to operate them by using the manual controls on the device itself and via an app on your smartphone. All work with digital assistants—such as Amazon Alexa, Apple’s Siri, and Google Assistant—so you tell your sprinkler system what to do. Think about the most convenient way for you to control your sprinkler system, and be sure to check for those features when you shop.
5. Not All Controllers Are Weatherproof
It’s somewhat surprising, but only two of the controllers we’ve tested are weatherproof. The rest either have to be installed indoors or you have to purchase an additional weatherproof housing for them, which cost about $30 for the models in our tests.
3 Superb Smart Sprinkler Controllers
Here are three of the best smart sprinkler controllers from our ratings, arranged in alphabetical order. CR members with Digital Access can read ratings and reviews for each one. All of them feature the EPA’s WaterSense certification and come in multiple versions for varying numbers of zones.