Let this robot weed your garden

Set it, leave it, and walk away.

I was intrigued by the Tertill and its claim that it could remove weeds and not the plants I wanted to keep. 

Ideally the Tertill is designed to move around crops, especially in a large raised bed. I interplant heavily in my garden, so I decided to get creative and see if it would work in other scenarios as well. What started out as a novelty (a weeding robot, cool!) turned into a device that I really enjoy. 

Here's how it works: It knows that a certain height of emerging plant is unwanted, so it automatically trims it. For best results, you'll want to make sure the area is weeded first, and the plants that you want to keep are either larger size or protected by the included guards if they are still emerging from the soil. Once the plants reach a certain height, Tertill will work around them. The device does a good job of navigating around taller seedlings and established plants.

According to the creators: "Tertill has ... specially designed wheels that churn up the top layer of soil, keeping weeds from sprouting — much like a well worn path. If any weeds do sprout, Tertill chops them down with its onboard string trimmer. Even if the weed sprouts again, Tertill will keep chopping it down until it gives up and dies. In an independent study, the Cornell School of Agriculture found Tertill's method of weeding as effective as hand weeding."  

So, how does it work?

Each year, there are portions of the garden that get out of my control. Two of these areas are the front path that cuts through my garden and underneath the bird feeder station in the back garden. Inevitably, plants that have self-seeded will start to grow and by mid-summer, those areas are looking a bit scraggly. But this year, I've put the Tertill in charge of those domains, and the spots are clear. 

In the first testing location, the dirt path, I used the included plant guards to protect a border of grape hyacinths (muscari) growing along my front path that I wanted Tertill to avoid. I installed the guard (just pushing it into the ground) and the height of the guard notified Tertill that it was time to turn around (this was especially useful when the plants were still emerging from the soil). 

I put the robot to work in a raised bed with garlic, a rose and a mum for its second trial. It successfully avoiding the established plants and kept new weeds at bay.

Next it was on to its final location underneath the bird food station in the back garden. I left it outside throughout the summer weather (including heavy rainstorms) and I cleaned it off easily with the garden hose and paper towels when needed.

Here's a quick recap on the three areas that I left Tertill in charge of. (Each spot was trialed for a month.)

Key Takeaways

What it does:

• It runs on solar power to maintain weed-free areas in the garden. 
• It is weather-proof, so it can stay outside in the rain and other bad weather conditions. (Bring it in for winter.)
• You can set up dividers to keep it in a selected area, or as in the case with my dirt path, the brick border was tall enough to keep it in check. Otherwise it will continue to wander.

What it will not do:

• It needs to start off with a weeded area to function best and maintain the weed-free area. It is not meant to be put into a weedy area to whip into shape. 

Ideal spot:

• Large, flat vegetable patches in rows would benefit the most from this device, but it will run in control areas where there are bare soil spaces to maintain. Avoid hilly areas. 

Price:

• Available on the Tertill website for $349, with free shipping. 
• UPDATED 1/14/24: This product is also available on Amazon and I've included it in my Plant supplies and tools list. As an Amazon Associate I earn from qualifying purchases.

Final thoughts:

The Tertill took care of areas of the garden that I often neglect due to other garden priorities. I started to take for granted that the Tertill would take care of these areas so they do not look overgrown. This is a fun garden gadget that will work in contained areas, and as a bonus, keep the neighborhood cat out of your garden. 

I was sent a Tertill to demo and evaluate in my garden earlier this season. Observations above are my own. 

Originally published Sept. 7, 2021. Updated January 14, 2024.