What to know before buying a robotic lawn mower

TAMPA, Fla. - Researchers with the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) studied some of the earliest robotic lawn mowers, which cut at 2.4 inches, to see if they could maintain St. Augustine grass when run daily.

To their surprise, daily mowing at this height did not ruin this hearty turf.

"Honestly, it kind of surprised us that Floratam, which is one of the older varieties that typically needs that higher cut, that it was able to perform at that," Dr. Bryan Unruh, professor and associate center director for the UF/IFAS West Florida Research & Education Center. "We don't necessarily know all of the details or all of ‘the why’ it did this."

Florida turf study

Dig deeper:

Experts say one reason could be because robotic lawn mowers – that glide over the yard every day -- provide a much gentler trim than a massive weekly chop, overall stressing the grass less.  

"And so by eliminating the vertical growth, it forced the grass to grow more in a horizontal (way) and so it was much more dense," Unruh added.

But with newer models of robotic lawn mowers now on the market, UF/IFAS experts suggest sticking to that golden rule of height.

"Again, the mower that we were testing at the time was limited to that 2.4 inches. We've seen the more modern robotic mowers that allow for that higher height of cut -- they perform just as fine," Unruh said. "We can keep them at the recommended heights of cut."

Check for outdoor hazards

What they're saying:

While robotic lawn mowers may reduce labor, experts say homeowners using this technology must monitor docking stations for specific outdoor hazards, including fire arts.

"We know fire ants are kind of drawn to electrical sources. You have the docking station that is out there. We have seen fire ants mound up in the electronics," Unruh explained. "And so it's just a matter of using a fire ant bait in and around that docking station."

They also suggest adding protection from lightning.

"I would make sure that wherever you're plugging your docking system in, to make sure that you're using a ground protection, lightning protection device in addition to the mower," he added.

Bay Area landscapers point out that robotic mowers may still require some manual labor to maintain a healthy yard.  

Trever Hickman of Guaranteed Green Florida noted that any grass cuttings left behind should be bagged.

"It's not going to bag the clippings. It's not going to take them away. It's not going to put them in the trash for you, and it's going to leave behind cuttings," Hickman said of robotic lawn mowers. "And that gets to blocking the roots from getting water."

And with yards already starved for water in current Tampa Bay conditions, residents can't afford to make matters any worse for their struggling lawns.

"Cutting it more often isn't bad if you're cutting it at a high height. A lot of mistakes people make, they want to cut it too often at a low height. And that's what ruins the grass. That's what gets more of the brown and more of the roots’ exposure. And that'll kill the grass eventually in those spots," Hickman added.

Tampa