Robotic Lawn Mowers: Pros and Cons for Gardeners

Suzanne Matta’s phone pings with an alert. Rosie is upside down. A glance at the app finds where in the yard Rosie is stuck, and Suzanne runs outside. Rosie is catawampus under a big spruce.

“Oh my gosh, Rosie, are you okay?” Suzanne helps the little robot off a root. After checking that Rosie’s four wheels touch ground, Suzanne taps a button, and Rosie toddles off to continue her silent work.

Rosie is not a living creature, but a robotic lawn mower about the size of a tortoise. To Suzanne, who refers to the machine as ‘she’, Rosie is a much relied upon member of the household that feels very much like a pet. Suzanne named it Rosie after the robotic maid in the 1970s cartoon The Jetsons. A quasi-intelligent machine helping around the house? Far out. And Rosie helps quite a bit. The robot mows nearly an acre surrounding the Matta home.

Robotic mowing is not a new concept —a model was patented in 1972—but it hasn’t been widely adopted in the United States. It certainly costs something to buy the equipment, and the installation process is not that easy, especially for models that require boundary wires. It helps to be a bit tech savvy and willing to dig around on the Internet to troubleshoot the inevitable glitch. There is also a big gap in the market for servicing the equipment and providing homeowners with support. Still, there are situations where it makes sense to invest the funds and effort to set it up.

For Suzanne and Frank, it was a strategic decision to get Rosie. They thoroughly enjoy the space and privacy that their large property affords, and until now Frank has done all the mowing on their five acres.

“We haven’t hired a landscape service and would prefer not to do so,” explains Suzanne. “Until we found the robot, we hadn’t figured out what we will do about all the mowing if Frank becomes unable to do it.”

The solution to that problem appeared in 2016. Suzanne was watching an episode of This Old House in which the hosts were installing a robotic mower and showing how it worked.

“Something clicked in my mind. I realized ‘That’s it!’” Suzanne snaps her fingers. She asked Frank to watch the episode, then they went into “research mode” about which model to buy and how to set it up. They chose a Husqvarna 450 XH, the largest model available to homeowners at the time. Now it’s their fourth season with Rosie on the team, and Suzanne says they will never go back.

Rosie mows 24/7—even in the rain—except when it needs to recharge. It finds its own way back to the docking station for that. Frank still cuts the other four acres with his tractor, but those areas require less frequent care, being farther from the house.

Related: Read about battery-powered lawn and garden equipment.

“There are so many good things about robotic mowing,” says Suzanne. “Here’s a big one: Rosie works while we are traveling, so it’s a security feature for us. By keeping the yard around the house maintained, she makes it look like someone is home. Also, since she is so light there are never any heavy mower tracks on the lawn during a wet season. Plus, the grass is noticeably healthier in the areas that Rosie covers.”

The constant mowing returns tiny clippings to the lawn where they quickly decompose, offering a free source of nitrogen to the roots. This reduces the need to fertilize the lawn.

“The logic of the robot is incredible,” said Frank. “Her mowing pattern is random. As she crisscrosses the yard, she will find a missed tuft and go get it.” During this random crisscrossing, the robot leaves no lines in the grass. Suzanne offers a big caution here:

“Understand it is not a conventional mowing situation. There are no stripes, so if you’re into that, forget it.”

While Suzanne encourages anyone who is curious about robotic mowing to investigate it, she notes that Rosie does have limitations. The robot can only mow contiguous areas of the lawn that can be outlined with a boundary wire. It can’t cross a driveway or sidewalk. And there are some areas on the Mattas’ property that are too steep for her to climb, even though they upgraded to larger tires, which can better handle hilly terrain.

Suzanne and Frank learned the rough spots in the lawn that Rosie had a hard time with, and they got rid of them. They smoothed out certain places and put boundary wire around a particularly rocky area where the machine tended to get stuck. Also, it was a monumental task to install that acre of boundary wire. Frank enlisted a friend to help, and they eventually got it done.

Rodents can and do eat the wire. Tracing the span of boundary wire to find a miniscule break is a bit of a challenge. But Suzanne, doing her research, found “a neat trick to finding the cut. Get out your transistor radio and turn the dial to where you only hear static. Walk around the boundary with it on. The noise stops when you come within a foot of the break.”

Lack of support is the biggest challenge. Mostly they’ve had to DIY it. Even with Suzanne’s willingness to research, there are a few problems they haven’t yet solved. For instance, the boundary wires don’t play well with the wires of the electronic fence that keeps their dog in bounds. Suzanne’s extensive research has yet to yield a solution to that one. Luckily, he is well trained.

Still, they would never go back. For the Mattas it’s about the security, convenience and consistency. From the time Rosie comes out of storage in May to when the leaves start to fall in late September, the lawn always looks freshly mowed. It’s a wonder more folks don’t have a Rosie of their own.

Image credit: Mechanicalcaveman.com