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Tertill Review: The Robot Weeder

Derek Hales

Written By: Derek Hales

Updated on:

An Automatic Gardening Assistant

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Tertill Weeding Robot

The Terill weeding robot is a moderately sized robot designed to live outside in your garden bed. It is waterproof, weather-resistant, and solar powered. Tertill is designed to run autonomously, cutting weeds as it finds them and skipping over larger plants that you want to keep.Check Price

Pros

  • Great way to enjoy the garden more and weeding less
  • Unique concept with virtually nothing else like it
  • Grow Together bundle includes stickers and markers for a fun family activity
  • Solar powered and weather-resistant, making it virtually maintenance free

Cons

  • Pretty basic app with limited features
  • Only covers 200 square feet

Scoring

The Weeding Robot
  • Design - 95%
    95%
  • Performance - 95%
    95%
  • Quality - 96%
    96%
  • Usability - 98%
    98%
  • Value - 96%
    96%
96%

Summary

The Tertill weeding robot is designed to cut down weeds before they have an opportunity to invade your garden. It comes with plant stakes so you can easily partition off small plants that you want to keep, otherwise it will eliminate any plant that is 2″ or less. It is weather-resistant, waterproof, and solar-powered you can sit it outside and let it do the dirty work. In terms of size, the Tertill is smaller than a traditional robot vacuum, but quite a bit taller. The taller height makes it possible for the robot to traverse over rocky terrain or across muddy rows. Overall, the Tertill is a good option for gardeners who want to spend less time pulling weeds.

Tertill Design

The Tertill weeding robot is a unique solution to a problem that most gardeners face—how to get rid of invasive weeds.

Tertill robot weeder
Tertill robot weeder

The Top

The top of the Tertill robot weeder has a solar panel charger that allows the robot to sit outside all year long without ever needing to charge up.

Top of the Tertill robot weeder
Top of the Tertill robot weeder

All the energy it needs it will get from the sun, which makes the whole setup pretty maintenance free.

The Underside

The bottom of the Tertill robot has four sharply angled wheels and a spinning single-arm nylon weeder.

Underside of the Tertill weeding robot

Other than those two elements the rest of the underside is pretty simple.

Tertill wheels
Tertill wheels

The simple design helps this robot to conserve energy and keep its waterproof design.

How Does It Work?

This weeding robot works by being placed in a contained portion of a garden. It will required raised perimeter edging or some other barrier to stay inside of the garden.

Tertill weeder string
Tertill weeder string

It charges up using energy from the sun and once the battery is charged it will begin weeding.

The Tertill drives around the garden autonomously. There is no fancy mapping technology or any way to set up virtual boundaries.

  • When the robot approaches a plant that is less than 2″ tall, it chops.
  • When it approaches a plant that is larger than 2″, it saves in.

What if the plant I want to save is a seeding?

If your plant is newly growing, you can put a wire barrier around the plant to tell the Tertill that it is a good plant you want to save.

Light display on the Tertill weeding robot
Light display on the Tertill weeding robot

The concept is that by cutting the weeds to the ground every day, there is no reason to “pull the weeds”. Eventually the unwanted plants will run out of energy and die off.

Also, because the clippings are so small when they are cut, you don’t need to worry about bagging them up for displosal. The weeds will simply shrivel up and die up into the soil, turning into nourishment.

How Big is the Tertill?

The Tertill is quite a bit smaller than most robot vacuums, but it is taller. Unlike robot vacuums (which have to navigate under furniture), the Tertill’s biggest obstacles typically lie on the ground.

The four angled wheels are positioned so the robot can navigate uneven garden terrain and effectively locate the weeds and other plants in question.

Profile view of the Tertill weeding robot
Profile view of the Tertill weeding robot

The Tertill is:

  • 8.25″ diameter
  • 4.75″ tall
  • 2.7 pounds

For comparison, the average indoor robot vacuum is approximately 12-13″ wide and 3-3.5″ tall.

What’s in the Box?

Wondering what’s in the box? The Tertill actually comes with a pretty wide assortment of parts and accessories. For this review, we received and tested the Grow Together bundle, which includes a number of extras.

Here’s the exact breakdown:

Accessories and parts with the Tertill weeding robot

Plant Guards

  • protects individual plants or rows of plants

Weeder String

  • used on the underside of the robot to cut the weeds

Plant ID Stakes

  • helps identify your plants

Robot Stickers

  • fun way to add some character to your robot

Acrylic Markers

  • for marking plant names on the stakes

Instructions

  • outlines the details of how to use the Tertill and more

Performance

To test the performance of a robot vacuum, we have a series of tests we run, but the Tertill is not your ordinary robot.

So we had to develop a new test and for this test, we’d need a garden.

Our Test

We made a small garden bed and got to work. Here was the process:

  1. Create garden bed with raised perimeter blocking.
  2. Plant
Tertill garden - at start
Tertill garden – at start

We planted carrot seeds in the 3 rows that you can see marked above. And to keep those seeds protected, we used the metal plant guards provided.

The guards are definitely an important step to ensure that the robot doesn’t accidentally run over the seedling plants after they sprout.

Carrot Seeds

Tertill garden - planting carrots
Tertill garden – planting carrots

Plant Guards

Tertill plant guards in use at the garden
Tertill plant guards in use at the garden

How big of a garden can it cover?

The Tertill can effectively maintain a garden up to 200 square feet.

It’s not an enormous space, but for most casual gardeners, that area coverage would be sufficient.

The Results

Our first result is a bit of a sad one…nothing ever grew in our garden. Either our soil was bad for the carrots, the weather was poor, or maybe my wife and I are just inept gardeners (most likely).

In any case, we were not able to test the Tertil removing weeds in our contained garden bed.

As a result, we moved on to a larger test.

Testing Usability & Weeding

Since our garden was a failure, we moved onto testing the Tertil in our larger backyard.

Tertil on rocks and concrete
Tertil on rocks and concrete

Technically, this is not how the Tertil is recommended to be used. As it really needs a confined space to be most effective.

Even so, we wanted to let the Tertil loose in our backyard to find out:

  1. If it could navigate over various obstacles
  2. What sort of objects it would get stuck on
  3. If it could actually remove weeds

#1 – Navigation

In terms of navigation the Tertil did great. Our backyard is around 0.5 acre and over the course of several days I would find it at various locations around the yard.

Tertil driving on thick grass
Tertil driving on thick grass

It had no trouble dealing with the various surface types in my backyard, which include rocks, small barriers, trees / tree roots, larger plants, concrete, dirt, grass, pool decking, and more.

#2 – Getting Stuck

The only area it struggled with was some of our tree boxes. It was able to come over the top of the box to get inside, but once inside it couldn’t escape. Even so, it’s hard to complain too much about that.

Tertil stuck in a tree box
Tertil stuck in a tree box

Beyond this issue, it was able to handle all of the other yard obstacles and surfaces without any issues.

#3 – Removing Weeds

Tertil does a good job at removing weeds, provided they are small. Which is really how the whole robot works. Any plant over 2″ tall it views as a plant you want to keep (whether it’s a weed or not).

Tertil wedding robot
Tertil wedding robot

In my view, it’s more about weed prevention. If you have weeds already established you’ll likely need to remove those first and then set Tertil to patrol and prevent future weed growth.

The Death & Rebirth of Our Tertil

In January we had a huge sleet and hail storm (in addition to rain), which is a rarity in Phoenix. As a result, our Tertil had stopped working and I originally wrote here that it was dead.

However, it seemed it just needed a reset and a few days in direct sunlight.

With that, it started working and is again patrolling my yard high and low in search of woods. So our test continues!

Setup & Usability

Setup and usability of the Tertill is easy. It’s solar-powered and pretty autonomous so all you need to do is place it in the garden and you’re good to go.

The App

There is also an app that integrates with your smartphone if you want some additional features. But I will add, the app feels a little underdeveloped.

It is able to tell you the basics, like how much battery is left on the robot, outside temperature, and solar power as well.

Screenshot from the app - Tertill weeding robot
Screenshot from the app – Tertill weeding robot

I’d like to see some additional information about performance, the number of weeds removes, working time, etc.

It is possible that these features will continue to develop, but right now the app is pretty basic.

Using the Tertill

After the initial setup, daily use of the Tertill is basic. It charges itself from the sun and when it has enough energy, it will run a weeding cycle.

Because it is able to cut the weeds daily, they are going to be quite short and easier to manage.

Maintenance

Keeping the Tertill running smoothly mainly just involves replacing the weeding nylon spinner as needed.

The frequency of those tasks can change based on use.

Aside from the weeding, there is minimal other maintenance tasks.

There is no weed bag to empty and no battery to manually recharge. Doesn’t get much simpler than that.

Is the Tertill a good value?

So all things considered, is the Tertill weeding robot a good value?

For casual gardeners with a relatively small area coverage and limited time on their hands to de-weed, the Tertill could be a good option.

Spinning weeding arm on the Tertill
Spinning weeding arm on the Tertill

The value of this product will be the highest for users who really despise weeding or simply don’t have the time to do it. It has a “set it and forget it” approach which makes the Tertill attractive for novice gardeners.

If you have a large garden, you may find that the Tertill isn’t powerful enough to cover the entire area.

Tertill Specifications

Specifications 
TypeWeeding Robot
ManufacturerTertill
ModelWeeding Robot
Diameter8.5"
Height4.75"
Weight2.7 lbs.
Floor TypeOutdoor; dirt
Digital MappingNo
ReturnsVaries by retailer
Warranty1-Year limited
PriceCheck Price

Should You Buy the Tertill?

I would recommend the Tertill if you want the following in a weeding robot:

  • Self-charging: It’s pretty nice that you can leave this robot outside and it will charge itself up in between run cycles. Furthermore, it is also waterproof and weather resistant so the elements won’t be an issue.
  • Up to 200 sf coverage: If you have a small garden approx. 200 sf, the Tertill could be a good option. Gardens larger than this will need a 2nd Tertill. Each Tertill can cover 200 square feet.
  • Reasonable price: Considering that you can leave this robot outside and it does the dirty work for you, most people would probably consider the Tertill to be a good value. Especially when you consider the value of not having to de-weed your garden and potentially increase overall yield in your garden. There are a lot of things to like about the Tertill weeding robot.

To learn more or to buy the Tertill weeding robot, you can check it out here.

Changelog

  • March 3, 2021 – Our Tertil wasn’t dead. We were able to get it working again and it’s running normally now. Updated our content accordingly.
  • February 26, 2021 – Updated the page based on our usability tests.
  • December 22, 2020 – Initial version of the page was published.

About Derek Hales

Derek HalesDerek Hales is the Founder and Editor-in-Chief of ModernCastle.com. He has been featured in Fast Company, Reader's Digest, Business Insider, Realtor.com, She Knows, and other major publications. Derek has a Bachelor's Degree in Business Administration from Kansas State University. Hales has been testing and reviewing products for the home since 2014.

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2 Comments on “Tertill Review: The Robot Weeder”

  1. So would this product be good for a small grassy (sodded) patch that l want to keep free from dandelions etc., or would it destroy the grass too?

    Reply
    • In theory, yes, though it’s not really designed for that. As long as the grass is 2″ or more it will leave it alone. Any grass shorter than that it will view as a weed and try and cut it down.

      Tertil reached out to me regarding this comment to inform me that the Tertil will not work on grass at all. At best, it will just cut some of your grass down.