The best string trimmer for tall grass is a high-voltage cordless model with a 15-inch or wider swath, or a gas straight shaft in the 22cc-and-up class. Both push enough torque through a dense mat that the head does not stall. If the growth contains woody stems, neither is enough and you need a brush cutter.
Grass that has passed roughly knee height changes the job entirely. A light-duty trimmer drives its line into a wet mat of stems, the head bogs, and the motor either smokes or quits. That is the complaint that shows up over and over in lawn and landscaping forums: not that the tool is weak in general, but that it dies the moment the line is properly buried.
So we judged all ten picks below on one thing first: how much of that buried line the tool can keep spinning. Runtime, balance, swath width and line handling matter, but they are tie-breakers. If you cut regularly, none of this applies to you and a small suburban trimmer will serve you for a decade. The moment you have let grass get away, the maths changes.
Table of Contents
Top 3 Best String Trimmers for Tall Grass (October 2026)
EGO ST1521S 15 in POWERLOAD
- 56V brushless power
- POWERLOAD auto line feed
- Carbon fiber split shaft
EGO ST1623T 16 in Line IQ
- Widest head in the group
- Auto-sensing Line IQ feed
- Telescoping shaft
All 10 String Trimmers for Tall Grass Compared in 2026
| Product | Specifications | Action |
|---|---|---|
| EGO ST1521S 15 in POWERLOAD |
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Check Latest Price |
 DEWALT DCST922B 20V XR |
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Check Latest Price |
| EGO ST1623T 16 in Line IQ |
|
Check Latest Price |
 BLACK+DECKER LST522 20V |
|
Check Latest Price |
 Makita XRU23Z 18V LXT |
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 DEWALT DCST972X1 60V |
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Check Latest Price |
| BLACK+DECKER LST300 20V |
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Check Latest Price |
 WORX WG183 40V |
|
Check Latest Price |
 RYOBI RY40250 40V |
|
Check Latest Price |
 WORX WG173 20V 3-in-1 |
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Check Latest Price |
How We Judged Trimmers for Overgrown Grass
Every tool here was assessed against the same five criteria, in this order. Cutting power in buried grass came first, because a trimmer that stalls has failed the only test that matters for this topic.
Second was runtime in hard conditions rather than the advertised figure. A battery that delivers an hour on a lawn edge and twenty minutes in chest-high growth is a different product from one that holds up in both.
Third was weight and balance across a full session, not the first five minutes. Straight shafts are heavy by design, and where the mass sits relative to your hands decides whether you can work an afternoon.
Fourth was line handling, since reloading in the middle of an overgrown field is miserable. Fifth was value, judged on the whole ownership picture including batteries, fuel mix and replacement line.
Owner evidence shaped the notes throughout. Forum discussion around these tools is unusually direct: people report years of ownership, specific failure modes, and the exact line gauge they run. We have used that language rather than press-release language wherever the sources allowed.
1. EGO POWER+ ST1521S 15 in POWERLOAD — Best Overall for Tall Grass
EGO POWER+ String Trimmer, Battery Powered, 15″ Trimmer for Weeds and Grass with POWERLOAD and Carbon Fiber Split Shaft, Includes 56V 2.5Ah Battery and Charger – ST1521S
56V cordless
15 inch swath
7.3 lb
56V 2.5Ah battery included
50 minute charge
Pros
- Holds speed with the head buried in long growth
- One-button POWERLOAD line reload
- Carbon fiber split shaft
- Quiet with no fumes or pull start
Cons
- Premium price bracket
- Battery and charger add-ons cost extra
- Spools run out fast in very dense growth
The ST1521S is the one we kept reaching for. Fifty-six volts of brushless power, a 15-inch head and a carbon fiber split shaft add up to a machine that stays at speed when the line is genuinely buried, which is the whole test. Owners describe exactly that in lawn forums, calling EGO cordless trimmers very powerful and singling out the brand for heavy brush and tall weeds rather than general trimming.
The POWERLOAD head is the feature that changes a tall-grass workflow. You push the button, the spool rewinds, and you are cutting again in a few seconds. On a property where you will feed line five or six times an hour, that matters more than almost any other spec on this list.
The included 56V 2.5Ah pack is the weak point of an otherwise complete package. Chargers take around 50 minutes, so on a big lot you want a second pack cycling while you work. The 5800 rpm head speed and the carbon fiber shaft, which carries a lifetime warranty, handle the load well.
The split shaft folds down for storage, which matters if the shed is tight, and the whole tool is light enough at 7.3 pounds to swing all day. It is one of the few cordless machines here that does not feel punishing after an hour of reaching into overgrown grass.
Noise is another quiet advantage. There is no exhaust, so you can run it early in the morning next to a property boundary without the neighbour complaint that comes with a two-stroke. For a lot in a residential area, that alone is a reason to pick cordless.
The honest limitation is line consumption. Owners report burning through spools faster than expected in very dense growth, and replacement spools add to the running cost. We would budget a spool per large session rather than per year.
Who the EGO ST1521S suits
This suits anyone whose grass gets away from them once or twice a season and who does not want to mix fuel. It is the strongest all-round pick for knee-to-waist-high growth, wooded edges and fence lines, and it is the model we recommend to someone who asked once and never again what to buy.
It also suits households that already own EGO 56V ARC Lithium batteries, since the platform is shared across the range. If you run one battery, you can run any tool on it.
Where the EGO ST1521S falls short
It is not the right tool for stems thicker than about a pencil, and it is not the right tool if you have only a small lawn that you cut every week. A 12-inch light trimmer is cheaper and kinder to the shoulder in that situation.
Nor is it the right tool for a full day of commercial work without spare batteries on hand. Owners running acreage on one pack will spend more of the session charging than cutting.
2. DEWALT 20V MAX XR DCST922B — Surprisingly Strong for 20 Volts
DEWALT 20V MAX* XR String Trimmer, 14-Inch, Tool Only (DCST922B)
20V MAX XR cordless
14 inch swath
9.2 lb
6000 rpm
tool only
Pros
- Handles thick brush and small woody stems
- Accepts 0.105 in line
- Folding hinge for storage
- QuickLoad spool
- Quiet early-morning operation
Cons
- Battery and charger sold separately
- Front-heavy balance tires the forearm
- Small debris guard throws more material
- Drains batteries fast on large properties
This is the tool that convinces people the voltage rule is a rough guide rather than a law. Owners routinely describe it as a deceptively powerful 20V machine that rivals higher-voltage gas units on thick weeds, and the 6000 rpm brushless motor backs that up. It accepts 0.105-inch line, which is the heaviest gauge most string heads will take, and heavier line is exactly what resists being buried.
For someone with a DEWALT battery wall already in the garage, that headroom makes this the value pick in a 20V frame. A folding hinge collapses the shaft for storage, and the QuickLoad spool cuts line changes down to a few seconds.
It is sold as a bare tool, so the battery and charger are a separate decision. Owners running large properties report that standard 20V MAX packs drain quickly in heavy growth and recommend the XR and Power Pack packs instead, which changes the math on how many you need.
The balance is the recurring gripe. At 9.2 pounds with the motor at the cutting end, weight sits forward of your hands, and reviewers flag forearm fatigue over long sessions. If you are clearing a hillside, that is worth planning a strap for.
The small debris guard is the other complaint, and it is a real safety point. Owners report more thrown material than with larger guards, which matters in overgrown ground where you cannot see rocks and old fence wire under the grass.
A minority of buyers also report premature motor failure, so it sits at 4.4 stars across more than four thousand reviews rather than higher. That volume of long-term owner feedback is worth more than a perfect press score.
Who the DEWALT DCST922B suits
It suits existing DEWALT owners who need a second string trimmer and already know the platform, plus anyone who wants gas-class cutting ability from a cordless tool at the lowest voltage here. It handles knee-high growth and light woody brush well when you keep the tip moving.
It also suits anyone who wants heavier line without a gas engine. The 0.105-inch capability is the spec to look for if the growth has stems in it rather than just blades.
Where the DEWALT DCST922B falls short
The bare-tool format punishes anyone starting from nothing, and the front-heavy balance makes it tiring on long hillside jobs. It is also a two-battery purchase before the trimmer even runs.
For a small yard cut regularly, it is more machine than needed. Our edging-focused roundup covers lighter options better.
3. EGO POWER+ ST1623T 16 in Line IQ — Widest Head, Best for Big Overgrown Lots
EGO POWER+ 16″ Cordless Weed Trimmer with Battery and Charger – ST1623T
56V cordless
16 inch swath
7.5 lb
4.0Ah battery included
60 min runtime
Pros
- Wide 16 inch swath for tall grass and acreage
- Line IQ head feeds without bump tapping
- Telescoping shaft for different users
- 60 minutes on the included pack
- Battery recharges in 55 minutes
Cons
- Premium price bracket against 20V models
- Fewer customer review images than some peers
Sixteen inches is the widest fixed head in this roundup, and for acreage that have gone over, width compounds fast. Every extra inch of swath is fewer passes through growth that drags on the head. Owners rate it highly for clearing thick overgrown grass quickly for exactly that reason.
The Line IQ head is the smarter design of the two EGO feeds here. It senses the load and feeds line automatically, so there is no bump tapping, which owners elsewhere identify as a real annoyance and a common cause of scuffed lawns every time line is fed.
The included 4.0Ah battery is the larger of the two packs in this roundup, giving up to 60 minutes of runtime, and it charges in about 55 minutes on the supplied charger. That is a genuine improvement over the 2.5Ah pack in the ST1521S.
The telescoping carbon fiber shaft is the feature owners mention second most. It extends for tall operators and shortens for transport, which addresses the fit problem that taller users raise repeatedly in forums, where fixed shaft length is a genuine complaint.
A brushless motor keeps vibration low, which matters across a long session in thick grass where a vibrating handle blunts your control and tires the wrist.
It is still firmly in the premium bracket, so if the tall-grass job is occasional the ST1521S below makes more sense on cost. For someone clearing several acres every spring, the wider head earns its keep.
Who the EGO ST1623T suits
It suits rural property owners, vacant lots and anyone whose cleanup runs beyond a lawn. The wide swath and the sixty-minute pack mean fewer stops and fewer passes, and the telescoping shaft fits a household with different heights.
It also suits owners who want no fuel mixing and no pull start, but who will not tolerate a cord. Line that feeds itself matters most when the grass hides the head and you cannot feel the spool.
Where the EGO ST1623T falls short
It does not solve woody brush. Sixteen inches of nylon line still will not take a stem the thickness of a pencil, and no amount of width changes that.
For a single weekend of medium-height grass, the price is more than the job requires. Our budget pick covers that case.
4. BLACK+DECKER LST522 20V MAX 12 in — Top Rated for Regular Edging Jobs
BLACK+DECKER 20V MAX 12 Inch Weed Eater Cordless String Trimmer and Wheeled Edger Lawn Tool with Spool, 2.5Ah Battery and Charger Included, Lightweight, 2 Speed PowerDrive (LST522)
20V MAX cordless
12 inch swath
5.7 lb
2.5Ah battery included
2 year warranty
Pros
- Very light at 5.7 lb
- Converts quickly to a wheeled edger
- Automatic Feed Spool
- Two-speed control trades power for runtime
- Battery and charger included
Cons
- 12 inch swath is narrow for tall dense growth
- 2.5Ah capacity is modest on large properties
This is the honest answer for anyone whose grass never gets away from them. At 5.7 pounds it is one of the two lightest tools here, and buyers consistently pick out the low weight, the quick conversion to a wheeled edger and the automatic line feed as the reasons it holds a 4.5 rating across more than six thousand reviews.
The PowerDrive transmission adds torque at the line end, which lets it run 0.065-inch line competently through ordinary lawn edge and moderate weed growth. Two-speed control is the sensible bit: high for dense patches, low when you are edging a driveway and want the pack to last.
The Automatic Feed Spool dispenses line without bumping, which avoids the lawn-scuffing problem that bump heads cause. For edging around paths and patios, the wheel kit keeps the head off the ground and stops it digging in.
The 12-inch swath is the compromise. It is narrow, which means more passes on tall grass, and on a job where you are already fighting through thick growth, passes are what wears you out.
The 2.5Ah battery is modest too. It is fine for a suburban lot cut every couple of weeks and thin on the first visit to a lot that has been left for a season.
Two-year limited coverage is the shortest warranty in this group. That is a fair reflection of where the tool sits in the range.
Who the BLACK+DECKER LST522 suits
It suits small and medium yards, especially anyone who wants one tool for trimming and edging or who cares more about shoulder comfort than raw cutting power. At 5.7 pounds it is comfortable for a full afternoon.
It also suits a household that wants a kit complete on day one, since the battery and charger are in the box. For our edging-focused recommendations we cover lighter options in more depth.
Where the BLACK+DECKER LST522 falls short
It is the wrong pick for grass above knee height across a large area. The narrow swath turns one pass into several, and each pass re-buries the head.
If your overgrowth is a one-time problem, this tool will finish it slowly rather than beautifully. Buy for the tall-grass case instead.
5. Makita XRU23Z 18V LXT — Highest Rated Build in the Group
Makita XRU23Z 18V LXT® Lithium-Ion Brushless Cordless 13″ String Trimmer, Tool Only
18V LXT cordless
13 inch swath
9.2 lb
6000 rpm brushless
up to 1 hour runtime
Pros
- Highest average rating of the picks
- Brushless motor with no oil mixing or pull start
- High and low button plus variable speed trigger
- Up to an hour on an 18V LXT 4.0Ah pack
Cons
- Tool only so battery and charger are extra
- 9.2 lb sits on the heavy side for a cordless trimmer
This carries the highest average rating in the roundup at 4.6 across more than a thousand reviews, and the reason owners give is consistent cutting speed in overgrown grass rather than any headline feature. The brushless motor turns a 6000 rpm head with no starting cord and no fuel to mix.
Control is the story for tall growth. A high and low button plus a variable speed trigger lets you drop the speed in a thick patch to finish a cut cleanly instead of tearing stems, then hold high for open runs. On a long property that is the difference between a controlled pass and a stall.
Runtime is quoted at up to an hour on an 18V LXT 4.0Ah pack, which is the most generous battery figure in this group. Because the tool is sold bare, plan on buying that pack and a charger.
The LXT platform is enormous, and that is the real argument for it. If you run any other 18V LXT tool, the batteries are already on the shelf and the trimmer costs you a bare tool plus a few hours of your time.
Owners cite platform compatibility and quiet brushless operation as the leading strengths, which makes sense for anyone working near a house boundary early in the morning.
At 9.2 pounds it is the heavier end for a cordless trimmer. There is no folding shaft here, so storage is bulkier than the folding hinge design used elsewhere in this roundup.
Who the Makita XRU23Z suits
It suits LXT platform owners who want dependable cutting in tall grass without dealing with gas, and buyers who put build quality and long service life above headline specs. The rating reflects exactly that preference.
It also suits operators who want fine throttle-like control in thick growth, since the dual speed control is finer-grained than most budget trimmers offer.
Where the Makita XRU23Z falls short
Thirteen inches of swath is narrow for acreage. You will cover ground slowly, and the 9.2 pound weight makes that slower still.
Battery cost is the practical complaint owners raise most. If you are starting from nothing, buying two LXT packs is a significant part of the total.
6. DEWALT DCST972X1 60V — Highest Peak Speed and the Widest Adjustable Swath
DEWALT 60V Cordless String Trimmer with Battery & Charger Included, 17 Inch, Attachment Capable (DCST972X1)
60V cordless
15 to 17 inch swath
15 lb
8000 rpm
battery and charger included
Pros
- 8000 rpm is the highest peak speed in the roundup
- Swath adjusts between 15 and 17 inches
- Takes 0.080 dual line and 0.095
- Brushless motor
- Attachment capable platform
Cons
- Heaviest tool here at 15 lb
- Lowest star rating in the group with more one-star feedback
Sixty volts and 8000 rpm is the most raw cutting power in this roundup, and the adjustable 15 and 17-inch swath is the widest available here. Reviewers credit the voltage for getting through thick vegetation and like being able to narrow the path when the battery runs down.
The head runs 0.080-inch dual line and accepts 0.095, which is the right pairing for the tall-grass job. Heavier line resists being buried and cuts stems rather than bending them around, and the quick-load spool makes changes fast.
It is attachment capable on the DEWALT universal platform, so the same battery can drive a blower, edger or hedge trimmer. If you already own DEWALT tools, this is the one to build a platform around.
Fifteen pounds is the heaviest machine here and it is felt immediately. The battery is large, the shaft is long, and owners point to arm fatigue as the defining drawback on long jobs. A shoulder strap is close to mandatory rather than optional.
The 4.3 rating is the lowest in this roundup, with a higher share of one-star feedback than any other pick. Durability complaints about the head assembly show up repeatedly, and that is worth weighing against the power advantage.
The battery and charger are included in this package, which is unusual at this power level and removes one of the reasons people step down from 60V.
Who the DEWALT DCST972X1 suits
It suits owners with acreage, slopes and woody edges who want the strongest cordless cutting available and already tolerate a heavy machine. The adjustable swath lets you finish a thin battery on the last passes.
It also suits buyers building a single-platform tool set, since attachment capability turns the battery into a multi-tool investment rather than a one-purpose purchase.
Where the DEWALT DCST972X1 falls short
Weight rules it out for smaller operators, and the head assembly complaints mean it is not the first choice for someone expecting many years of hard service.
For occasional tall-grass jobs, the price and the mass are disproportionate. The EGO ST1521S gives more comfort for less.
7. BLACK+DECKER LST300 20V MAX — Best Value With the Biggest Owner Track Record
BLACK+DECKER 20V MAX String Trimmer and Edger 2 in 1, Cordless Weed Wacker with Auto Spool Feed, Battery and Charger Included, 12 Inch Steel Deck, Reduced Vibration (LST300)
20V MAX cordless
12 inch swath
5.7 lb
6200 rpm
2.0Ah battery included
Pros
- Most reviewed trimmer design in this roundup
- Light 5.7 lb frame with adjustable handle
- Automatic Feed Spool with no bumping
- Converts to an edger in seconds
- Wall mountable charging base included
Cons
- 12 inch swath is narrow for tall dense grass
- 2.0Ah is the smallest battery capacity included
More than nine thousand reviews make this the most thoroughly proven design here, and long-term owners point to the low weight, the instant edger conversion and the quiet operation as the reasons it stays in service. That volume of real ownership history is worth more to a buyer than any lab figure.
At 5.7 pounds it is one of the two lightest tools in the roundup, with an adjustable handle and multiple height positions. On a job that takes an hour, that weight is the difference between finishing and putting it down.
The Automatic Feed Spool eliminates bump feeding entirely, the POWERDRIVE transmission holds 6200 rpm, and the wall mountable charging base keeps the kit tidy in a garage. The included 2.0Ah pack carries a runtime improvement over the previous generation.
The 12-inch swath is the same limitation as the LST522 above, and it is the reason this is not our tall-grass pick. On chest-high grass, a narrow head means more passes and more time with the head buried.
The 2.0Ah battery is the smallest included in this roundup. It suits a lot you cut every few weeks, not a first visit to ground that has grown since summer.
Two-year limited coverage again places it at the entry tier, which is consistent with where it sits against the premium cordless picks.
Who the BLACK+DECKER LST300 suits
It suits anyone who wants a dependable, low-cost trimmer and edger for a fenced suburban yard and will keep on top of the grass. Owners in forums describe choosing cordless specifically for a small yard like this rather than for power.
It suits buyers who value a proven design over new features, and the included battery, charger and wall mount mean the kit works the day it arrives.
Where the BLACK+DECKER LST300 falls short
It is the wrong tool for tall grass at all. The narrow swath and small pack are exactly the two weaknesses that show up when growth is deep.
If you are replacing an underpowered trimmer because you want to cut taller grass, this will not solve the problem you are trying to fix.
8. WORX WG183 40V — Lightweight Kit With Two Batteries Included
Worx Cordless String Trimmer, 40V 13″ Electric Weed Wacker, WG183
40V cordless
13 inch swath
6.4 lb
7000 rpm
two 2.0Ah batteries included
Pros
- Two batteries and a dual charger in the box
- Light 6.4 lb frame
- Dual-exit cutting head for efficiency
- Automatic-feed spool
- Adjustable auxiliary handle
Cons
- Lowest average rating in this group
- Each included battery is small so runtime falls short of the 40V label
The selling point is simple: two batteries and a dual charger come in the box, so there is no second purchase and no waiting on a single pack while the grass grows back. At 6.4 pounds it is also one of the lighter options here, which matters in tall grass where the head is buried and you are levering against resistance.
The dual-exit cutting head pulls line out at two points rather than one, which improves cutting efficiency and wears the spool more evenly. A 7000 rpm figure sits higher than most of the cordless picks here.
The Power Share platform is shared across WORX 20V and 40V tools, so the batteries carry over to other equipment in the range.
The catch is the battery sizing. Each included pack is a small 2.0Ah unit, so the 40V label overstates continuous runtime and owners report short sessions in heavy growth. It is fine on edge work and short on a full lot.
The 4.2 rating is the lowest here, with a higher share of one-star feedback. Reviews point to weak torque in the heaviest growth and shortened runtime from the small cells rather than to build quality.
Thirteen inches of swath also puts it behind the wider heads in this roundup, so acreage work means more passes.
Who the WORX WG183 suits
It suits buyers who want a complete cordless kit at the lowest outlay and who work in short bursts with a battery always charging. The twin-pack arrangement removes the most common cordless complaint about waiting.
It suits anyone who feels weight more than power, since 6.4 pounds is manageable for an afternoon and the adjustable auxiliary handle helps set the grip.
Where the WORX WG183 falls short
It is not built for genuinely tall grass. Low torque in heavy growth and short runtime from small cells are the two limits owners name.
For overgrowth work, the money is better aimed at a 56V model with a larger pack. We would not pair this with a heavy property cleanup.
9. RYOBI RY40250 40V — Widest Gas-Platform Attachment Range
RYOBI 40-Volt Lithium-Ion Cordless Attachment Capable String Trimmer, 4.0 Ah Battery and Charger Inc
40V cordless
13 to 15 inch swath
13.9 lb
4.0Ah battery included
90 minute charger
Pros
- Gas-comparable power for overgrown growth
- Swath adjusts between 13 and 15 inches
- Accepts expand-it and universal gas attachments
- Variable speed trigger
- Reel-easy bump head reloads quickly
Cons
- Heavy at 13.9 lb so a strap helps
- Long shaft feels awkward in tight spaces
- Runtime in heavy growth falls well short of the advertised hour
The RYOBI is one of the few cordless machines here that accepts both its own expand-it line and universal gas attachments, so a single battery can run a blower, edger, cultivator or the gas-compatible tools in the range. For a property owner who wants one battery ecosystem, that breadth is the reason to pick it.
Owners also credit it with gas-comparable power in thick weeds. The adjustable 13 to 15-inch cutting width lets you trade path width for runtime, which is a sensible control when the pack starts to fade near the end of a job.
The reel-easy bump head reloads quickly, which matters when the alternative is winding a spool by hand in the middle of a field.
At 13.9 pounds it is heavy for a cordless tool, and the long shaft is awkward in tight spaces like around playground equipment or between flower beds. Owners specifically recommend a shoulder strap for long jobs.
Runtime is the honest problem. The 4.0Ah pack and the 90-minute charger are fine on paper, but owners report roughly 30 to 40 minutes of real work in heavy growth, well below the advertised hour.
The 4.2 rating reflects that balance: strong power, awkward handling, and a charger that will not refill quickly between sessions.
Who the RYOBI RY40250 suits
It suits owners with mixed yard equipment needs who want one battery to cover a range of tools, and who are already committed to the RYOBI platform. Gas-attachment compatibility widens the options further.
It suits people who can manage 13.9 pounds comfortably. Taller, stronger operators with acreage get a lot of machine for a cordless price point.
Where the RYOBI RY40250 falls short
Weight and shaft length make it tiring, and the recharge time means you are waiting 90 minutes to swap packs mid-job.
It also does not reach into brush. The forum consensus is clear that commercial-grade gas is what genuinely handles brush, and this is not that.
10. WORX WG173 20V 3-in-1 — Clever Multi-Tool, Middling in Deep Grass
WORX 20V 13″ 3-in-1 Cordless String Trimmer/Lawn Edger/Mini Mower, WG173
20V cordless
13 inch swath
6.6 lb
7600 rpm
4.0Ah battery included
Pros
- Trimmer
- wheeled edger and mini mower in one
- 7600 rpm brushless motor
- 7-position handle and telescoping shaft
- Wheeled edging support limits flying debris
- 4.0Ah pack included
Cons
- Line feed is awkward and users report breaks and spool tangles
- Runtime closer to 30 to 60 minutes in dense growth
- Charger left plugged in slowly drains the battery
The WG173 does three jobs: it trims, it edges on wheels, and it mows raised beds. That versatility earns it a place on a small property where you would otherwise own three tools, and the 7600 rpm brushless motor is genuinely quick for a 20V machine.
Owners like the quiet, light handling and the way the wheeled edging support keeps the head off the ground, which cuts down on flying debris exactly where you are working near paths and beds. The 7-position handle and telescoping shaft fit a range of users in one household.
Dual 0.065-inch line delivers more cutting strength than that gauge suggests, and the 4.0Ah pack is included with a charger, so the kit works out of the box.
The line feed is the most common complaint and the one that matters most for tall grass. Owners report the electronic feed breaking line and tangling the spool, and a head problem mid-job in overgrown ground is a bad afternoon.
Runtime on the 4.0Ah pack lands closer to 30 to 60 minutes depending on density, so pack count still decides how much ground you cover.
There is also a documented charging issue: the charger left plugged in slowly drains the battery, which matters if you store the tool charged between seasons.
Who the WORX WG173 suits
It suits small yards and allotment-style properties where trimming, edging and mowing raised beds all appear in one afternoon. Light weight and quiet operation make it good near neighbours.
It suits buyers already on the Power Share platform, where the 4.0Ah pack and charger work across other tools in the range.
Where the WORX WG173 falls short
Tall grass is where the awkward line feed bites hardest, because you will be feeding line constantly and the head stays buried. The spool tangles owners report are worse here than on ordinary edging work.
For deep overgrowth we would pick a wider head with a proven bump or auto-load system instead.
How Tall Grass Each Power Class Can Realistically Cut
Voltage and displacement map surprisingly cleanly onto grass height. Below about knee height almost anything works. Above it, the head starts staying buried, and that is where power class decides whether the job finishes.
20V cordless with a 12-inch swath: handles lawn edge and grass to about ankle-to-knee height. Past that you are re-passing constantly.
20V cordless with a 13 to 14-inch swath and brushless motor: knee height reliably, waist height in thin growth, especially with 0.080-inch line.
40V to 56V cordless with a 15-inch or wider head: waist-high grass as a matter of course. Chest height in stages, working top down.
60V cordless: the tallest grass any of these picks will take in one pass, and it accepts 0.095-inch line for stem-heavy growth.
22cc gas straight shaft: professional territory. Runs all day and takes on growth that stalls cordless tools.
27cc and up, or any harness-capable brush cutter: where tall grass stops being a string trimmer problem at all.
The rule that matters is the escalation point. If the stems are thicker than a pencil, or you see saplings and vine growth mixed into the grass, stop shopping for a bigger string trimmer and buy the next tool up.
How to Cut Tall Grass Without Bogging the Motor Down
Most trimmer stalls are technique failures before they are power failures. The head only cuts at the tip, so anything that buries the whole spool just creates drag.
Work from the top down. Take a foot to knee height off the top, clear the ground you can see, then take the next band. Trying to cut from the base buries the head immediately.
Keep the tip moving. Short sweeping strokes at a steady pace cut cleanly. Holding the head in one spot while the motor labors is what causes smoke and stall.
Sweep the full arc. Use the whole length of the cutting tip instead of grinding a narrow band. That is what the wedge shape is for.
Cut at a slight angle on fences. Thirty degrees off the fence line keeps your line off the wire and away from posts.
Slow down in the stems. On thick growth, drop to a lower speed setting and let the head pull through rather than forcing it.
Work in sections. Divide a lot into manageable strips. Finishing a strip you can see the end of is far better than disappearing into unmown grass.
Watch what is under the grass. Cut at walking pace in unfamiliar ground. Old wire, rocks and debris are thrown by every head in this roundup.
Clear a walkway first if the growth is deep. Fighting forward through chest-high grass without seeing your footing is how people hurt themselves, and most trimmer injuries we hear about happen in exactly that situation.
When a String Trimmer Is the Wrong Tool
If the stems are thicker than a pencil, or there are woody saplings, brambles and vine growth mixed into the grass, a string trimmer is the wrong tool. This is the most-asked question in lawn and landscaping forums, and the answer is consistent: move up to a brush cutter.
A brush cutter is the same basic machine with enough torque to run a metal blade. A three-tooth or four-tooth blade chews through stems that would snap nylon line, and a harness transfers the load so the machine stays controllable. The forum consensus is blunt: for tall grass and large weeds, commercial-grade gas is the answer.
There is a middle path. Several powerheads accept both a line head and a blade head, so one machine and one battery covers grass and light brush. That is worth checking before buying two tools.
Renting is also legitimate for a single clearance job. If the lot has not been touched in two seasons, a day of hire costs less than owning a machine you will use once. Professionals say the same thing about very heavy overgrowth: the limiting factor is usually operator stamina rather than the tool.
Trimmer Line Gauge Guide: 0.065 vs 0.080 vs 0.095 vs 0.105 in
Line diameter is the variable most buyers ignore and the one that most affects the tall-grass job. A thin line wraps around stems and snaps. A heavy line cuts them, and it also survives being buried.
0.065 in: light edging and lawn trim work only. Too thin for growth above the knee.
0.080 in: the sensible default for general use and the first step up into taller grass.
0.095 in: the heavy-duty choice for thick weeds, dense unmown grass and anything with stem structure. Most 40V and 56V heads handle it well.
0.105 in: near the top of the line scale. Excellent on stems, but only on heads rated for it and with a strong motor. The DEWALT DCST922B accepts it.
Square line cuts harder and frays less, which suits heavy work. Round line lasts longer and spools in more. Match the gauge to the head and never exceed what the spool allows; forcing thicker line onto a small spool causes the tangles owners complain about.
Line length matters too. Over-extending past the spool shroud makes the tip whip and cut less efficiently. Leave about four finger-widths of line showing at each side, and check the manual for the recommended length.
Buying Guide: Power, Shafts, Swath and Safety
Gas or cordless for tall grass. High-voltage cordless at 40V to 60V now matches mid-range gas on cutting power and wins on noise, fumes and starting. Gas still wins on all-day runtime, because a tank refills in under a minute while a battery may take 45 to 60 minutes. Professionals gravitate to commercial-grade gas straight shafts. For a lot you clear once a season, cordless is the better fit.
Straight or curved shaft. Straight shafts put the powerhead away from you, reach further into growth, and are the heavy-duty choice for tall grass and slopes. Curved shafts are lighter and easier in small yards but reach less far. Loop and bicycle handles improve control on long jobs and slopes.
Cutting swath. Wider means fewer passes. Over-extending the line past the shroud reduces efficiency, so match the swath to the grass rather than to the label.
Line feeding. Bump feed is cheap and universal but scuffs the lawn and needs the head off the ground. Automatic and auto-load heads feed themselves or wind on a button, which matters in tall grass where the head is buried and you cannot tap it. Auto-load is the feature owners single out most positively.
Balance and fit. Check total weight and where it sits. Taller operators ask repeatedly for the longest shaft available, and telescoping shafts solve the problem outright. A shoulder strap on anything over ten pounds is worth the money.
Reliability. Owner reports on this equipment are blunt rather than diplomatic. Threads ask which brands to steer clear of, naming Weedeater, Ryobi and Craftsman in the same breath, while ECHO and STIHL ownership is described as long-term value with reports of units that never failed. One ECHO SRM-225 long-term owner noted that the model, which is the most-mentioned in forum threads, seems to have issues in general. Treat every brand as mixed and check the specific failure modes: spool and head, carburetor, battery, switch.
Safety. Every tool here throws debris at high speed. Wear eye or face protection, closed-toe shoes, long trousers and hearing protection for gas. Keep clear of people and animals in the arc. Never cut where you cannot see the ground, and treat any fence line as live wire until you have confirmed it.
For keeping the rest of the yard tidy around those jobs, our picks for the best cordless string trimmers for edging cover the light end of this range, and our hedge trimmer guide covers shaping shrubs once the grass is down. If the rough ground is hard to reach on foot, our best power wheels for grass roundup covers getting through it first.
Frequently Asked Questions
What is the best string trimmer for tall, thick grass?
A cordless trimmer at 40V to 60V with a 15-inch or wider swath, or a gas straight shaft in the 22cc-and-up class. Both keep enough torque in the head that the line stays buried in long growth without stalling. Pair it with 0.080 to 0.095 inch line and cut from the top down.
How do I whipper snip tall grass without bogging down?
Cut from the top down in stages, keep the tip moving with short sweeping strokes, use the full arc of the cutting tip, and slow down in thick stems rather than forcing the head. Drop to a lower speed setting when the motor labours and clear a walkway first so you can see the ground.
What string trimmer do professionals use?
Commercial-grade gas straight shafts in the 22cc and up class, typically with a straight shaft, anti-vibration mounting and a harness. Professionals pick them because a tank refills in under a minute while a battery may take 45 to 60 minutes, so the tool never stops for the length of a working day.
Is a bigger trimmer line better?
For tall grass, yes, up to the limit your head allows. 0.065 in is for edging only, 0.080 in is the sensible default, and 0.095 in is the heavy-duty choice for thick weeds and dense unmown growth. Square line cuts harder and frays less; round line lasts longer. Never exceed what the spool is rated for.
When should I use a brush cutter instead of a string trimmer?
When stems are thicker than a pencil, or when saplings, brambles and vine growth are mixed into the grass. A brush cutter runs a three-tooth or four-tooth metal blade that chews through woody growth instead of snapping nylon. Some powerheads take both a line head and a blade head, which covers both jobs with one machine.
Are gas or electric string trimmers better for overgrown grass?
High-voltage cordless at 40V to 60V now matches mid-range gas on cutting power and wins on noise, fumes and starting. Gas still wins on all-day runtime because a tank refills in under a minute while a battery may take 45 to 60 minutes. For a lot cleared once a season, cordless suits most homeowners better.
The Verdict on the Best String Trimmers for Tall Grass
The EGO Power+ ST1521S is our pick for most people facing overgrowth, because 56 volts and a 15-inch head hold speed with the line buried and the whole thing stays light through a long afternoon. The EGO ST1623T takes over when the job is acreage, with the widest head here and a larger pack for longer sessions. The BLACK+DECKER LST300 is the honest answer for anyone who cuts regularly and never lets the grass get away.
Two things decide the rest. Match the line gauge to the growth, at 0.095 inch for anything stem-heavy, and cut from the top down in stages. Get those two right and most trimmers cope with taller grass than their owners expected.
And if the stems are thicker than a pencil, stop upgrading trimmers. Buy a brush cutter, or hire the job out for a day. That decision saves more time than any model on this list.
We keep these picks updated through 2026, and the cordless edging side of the range is covered separately in our cordless string trimmer roundup.