A tidy lawn often comes down to two tools that look alike but do different jobs. The edgers vs string trimmers question trips up plenty of homeowners, and the honest answer depends on your yard.
An edger carves the crisp vertical border along your driveway and sidewalk. A string trimmer cleans up the grass your mower cannot reach. Sometimes one tool covers both jobs, and sometimes it does not.
This guide breaks down what each tool does, how it works, and when you genuinely need both.
Key Takeaways
- Function: An edger cuts a vertical line to define borders along hard surfaces; a string trimmer cuts horizontally to shorten grass where a mower cannot reach.
- Mechanism: An edger uses a rigid metal blade that digs to root level; a string trimmer uses a flexible spinning nylon line.
- Versatility: A string trimmer can edge if you turn it vertical, but the line gives a less consistent border and wears out faster than a blade.
- Which to Buy: One good string trimmer covers most small, well-kept yards; add a dedicated edger for long borders or a first-time, overgrown edge.
What’s the Difference Between Edgers Vs String Trimmers?
Both tools keep a yard looking sharp, but they cut from different angles. Here is what sets them apart.
Edgers
Lawn edgers are precision tools built to create boundaries. You run them along hardscapes like driveways, sidewalks, and patios.
An edger drives a vertical metal blade through thick grass roots and soil, cutting down to root level. That opens a clean physical gap between your lawn and the concrete, and the blade makes a deeper, sharper line than a spinning nylon line can.
You will usually see three types:
- Manual Edgers: Shovel-like tools with a half-moon blade. They are cheap and quiet but ask for real elbow grease.
- Walk-Behind Edgers: These look like mini mowers. A larger 9 to 10 inch blade and a lever-locked depth keep the trench consistent, which makes them the pick for long or first-time edges. They are heavier and take up more storage.
- Stick Edgers: These resemble string trimmers but carry a vertical blade at the bottom. They are light and quick on edges you already maintain, though the depth can wander as your arms tire.
String Trimmers
String trimmers, also called weed eaters or whackers, are the finishing crew. You use them to cut grass your mower cannot reach.
Instead of a blade, they spin a flexible nylon line at high speed. That line whips through grass and weeds around obstacles like trees, mailboxes, and fences.
Power is the other choice to make. Gas trimmers refuel for effectively unlimited runtime and have the torque for heavy overgrowth, but they run heavier and louder. Electric string trimmers come corded, which are the lightest, quietest, and cheapest but tied to an outlet, or battery-powered, which roam free for roughly 30 to 90 minutes a charge and can bog down in the thickest weeds (Consumer Reports).
Bottom Line
Think of it this way. An edger cuts a vertical line into the ground to separate the lawn from the path. A string trimmer cuts grass horizontally to lower its height. Edgers define the shape; trimmers clean up the rest.
When to Use an Edger
Reach for the edger when you want a crisp, defined border. A mower cannot cut flush against concrete without risking blade damage, so grass creeps over the edge.
An edger slices through that overgrowth and cuts a shallow trench. This keeps grass roots from invading flower beds or working into cracks in the walkway. It does nothing for the health of the grass, but it sharpens curb appeal more than any other single tool.
Before you start, clear the strip of rocks, wire, and stray toys, and note where sprinkler heads and any exposed wiring sit so the blade does not catch them. If you plan to cut a deep trench, call 811 first to check for buried utility lines.
When to Use a String Trimmer
The string trimmer comes out right after you mow. You use it to tidy the spots the mower deck was too bulky to fit, like under decks, around garden ornaments, or along an uneven fence line.
It also handles tall weeds on rough ground before you mow. On a steep hill or a ditch where a mower cannot go safely, the trimmer is the tool that gets it done.
Top Tip
Wear safety glasses and long pants with either tool. Trimmers and edgers throw rocks and debris fast enough to injure, and about a third of the injuries they cause are eye injuries (Texas A&M AgriLife).
Edgers vs String Trimmers: Pros and Cons
You might want to buy both, but weigh the specific upsides and drawbacks against your budget and storage space first.
Edgers
Pros
Here is what a dedicated edger does well:- Cuts professional, deep separation lines.
- Keeps roots from creeping onto walkways.
- Metal blades are durable and shrug off thick overgrowth.
- Walk-behind models hold a steady depth and are easy to control.
Cons
Here is what holds it back:- It does one job, so it earns its space only if you edge often.
- Motorized versions are heavier and cost more.
- Manual versions wear you out on a large property.
String Trimmer
Pros
Here is why a string trimmer is a household staple:- Handles trimming, light edging, and small patches a mower misses.
- Light and easy to steer into tight corners.
- Replacement line is cheap and easy to find.
- Battery models are quiet and need little upkeep.
Cons
Here is what to keep in mind:- Held too low, it can scalp and damage the lawn.
- The nylon line breaks often against hard surfaces, so you feed it more.
- Flying debris is a higher risk than with a guarded edger.
Can I Use a String Trimmer As an Edger?
Yes, and many landscapers do it to save a tool and a trip to the truck. Turned vertical, a trimmer will cut a passable edge. Just know the honest tradeoff. The flexible line gives a less consistent edge than a rigid blade, it wears down fast against concrete so you feed more of it, and it takes practice to hold a straight line without gouging the dirt. For a small yard or an edge you already keep up, that is usually enough. For a long border or a first cut through heavy overgrowth, a dedicated edger holds its depth far better.
To flip your trimmer into edging mode:
- Turn the trimmer head 90 degrees so the line spins vertically (like a Ferris wheel) instead of horizontally (like a helicopter).
- Line the string path up with the gap between the grass and the concrete.
- Walk slowly along the hard surface and keep the trimmer steady. Let the line chip away the overhanging grass and a little soil.
- Point the debris shield toward your body so it deflects flying rocks away from your face.
FAQs
Edger Vs Trimmer: The Verdict
So which one deserves the spot in your garage?
If you can buy only one, get a good string trimmer. You will reach for it every week around trees, fences, and beds, and tilted vertical it edges well enough for most yards.
Add a dedicated edger when you want the crisp, professional line a spinning trimmer cannot quite match, or when you have long borders and a first cut through thick roots ahead of you. For a small, well-kept lawn, the trimmer alone often does the whole job.
