St. Augustine grass is a coarse, wide-bladed warm-season turf that spreads by stolons and grows hard through the summer. The best lawn mowers for St. Augustine grass are high-powered rotary or robotic models with a deck that lifts to at least 4 inches, a blade sharp enough to slice rather than tear, and enough torque to keep moving when the canopy is wet. Cut high, cut often, and never below 3 inches.
I spent several weeks reading owner feedback, deck specs and height ranges across ten walk-behind and robotic mowers, then sorted them against the three things that actually decide whether a mower suits this grass. What follows is the short version: the EGO POWER+ LM2135SP kit is the one I would put on a Floratam lawn in a humid coastal yard, and the gas and budget picks cover the rest of the range.
You can also start from our broader guides to the best self propelled lawn mowers and the best EGO lawn mowers if your yard is not St. Augustine specific. Everything below is scored against St. Augustine requirements only.
Table of Contents
Key Mowing Tips for St. Augustine Grass
Height: Set the deck to 3.5 to 4 inches, and never below 3 inches, because longer blades shade the roots and feed the stolons.
Sharpness: Replace or sharpen the blade every 20 to 25 hours, since a dull blade frays the wide blades and the lawn browns off within days.
Mower type: Use a rotary or robotic mower with lift capability; reel mowers cannot handle this grass.
Before you buy, it helps to know three things: how big the lawn is, whether you prefer gas or battery power, and whether the mower needs to reach 4 inches on a Floratam lawn or something shorter on Palmetto or Cobalt. That last point is the one that rules out the most mowers, and it is the first thing I checked on all ten.
Top 3 Best Lawn Mower Picks for St. Augustine Grass in 2026
EGO POWER+ LM2135SP Cordless Kit
- 7.0 ft-lbs cutting torque
- Up to 60 minutes on a 56V 7.5Ah battery
- Select Cut interchangeable blades
- Height range 1.25 to 4 inches
PowerSmart 22-Inch 150cc Gas Mower
- Briggs and Stratton EX625 engine
- Rear-wheel drive self-propelled
- 3-in-1 mulching bagging and discharge
Greenworks 80V Cordless Mower
- 80V brushless drivetrain
- 21-inch steel deck
- Covers up to half an acre per charge
All 10 Mowers Compared for St. Augustine Lawns
| Product | Specifications | Action |
|---|---|---|
| EGO POWER+ LM2135SP Cordless Kit |
|
Check Latest Price |
| PowerSmart 22-Inch 150cc Gas Mower |
|
Check Latest Price |
| Greenworks 80V Cordless Mower |
|
Check Latest Price |
 Greenworks 60V Dual-Battery Mower |
|
Check Latest Price |
 SENIX 22-Inch 201cc Gas Mower |
|
Check Latest Price |
 YARDMAX 22-Inch 201cc CVT Mower |
|
Check Latest Price |
 WORX WG760 40V Cordless Mower |
|
Check Latest Price |
 EGO POWER+ LM2114SP Cordless Mower |
|
Check Latest Price |
 Segway Navimow i105N Robot Mower |
|
Check Latest Price |
 BILT HARD 21-Inch 201cc Gas Mower |
|
Check Latest Price |
What Mowing Height Does St. Augustine Grass Need?
Mow St. Augustine grass at 3.5 to 4 inches, and never below 3 inches. At that height the wide blades shade the crown and the stolon roots, the canopy holds moisture through the afternoon, and the lawn blocks the light that lets weeds and brown patch establish. Cutting shorter exposes stolons to sun and drying wind, which is why a lawn that gets mowed too low often browns within a week.
UF/IFAS Extension guidance for the Gulf and Atlantic coastal South follows the same logic: this grass likes to be long, and it should be cut often enough that you never remove more than a third of the blade in a single pass. In peak summer on Florida lots that means two to three cuts a week, which is the number most owners in mower forums settle on.
How to set your deck to 4 inches in four steps
Park the mower on level ground and set the deck lever to its highest notch.
Measure from the lowest point of the blade tip to the ground with a ruler, not the lever position itself.
Drop one notch at a time until the measurement reads 3.5 to 4 inches, then check the same point at the front and rear of the deck.
Re-measure after every blade sharpening, because grinding the tip down changes the effective cut height.
Variety matters more than most guides admit. Floratam, the most common St. Augustine in Florida yards, is usually run at the top of the range near 4 inches, while Palmetto, Raleigh and Cobalt hold up fine a little lower, closer to 3.5 inches. If you are unsure which variety you have, start high and lower the deck a notch at a time over a few weeks.
One practical warning: many walk-behind mowers top out at 3 inches, and a few in this group stop just short of 4. If a mower’s published maximum is 3 inches it is the wrong machine for a Floratam lawn, and no amount of adjusting will change that.
Why Reel Mowers Fail on St. Augustine Grass
No, you cannot mow St. Augustine grass well with a reel mower. Reel mowers cut with a scissors action that needs a thin, fine, upright sward, and St. Augustine has coarse, flat, wide blades that fold over and spring back instead of standing up into the reel.
The result in practice is a lawn that gets pushed down rather than cut, then springs upright a few days later looking worse than before. Reels also struggle badly with the stolons that run across the surface, and the wet-clump problem is worse here than on almost any other turf. If you want the cut quality of a reel mower, that is a Bermuda or fescue lawn. For this grass, a rotary or robotic deck is the only realistic answer.
1. EGO POWER+ LM2135SP Self-Propelled Cordless Mower
EGO POWER+ 21″ Cordless Electric Lawn Mower Kit, Self-Propelled – LM2135SP
- 7.0 ft-lbs of cutting torque from a brushless motor
- Interchangeable Select Cut blades for mulching or high-lift bagging
- Touch Drive self-propel with a fingertip speed dial
- Height range reaches the full 4 inches St. Augustine needs
- Works across the whole EGO 56V ARC battery platform
- Single battery means large lawns need a swap or a charge break
- Blade swaps add assembly steps
This is the mower I kept coming back to. The 7.0 ft-lbs of cutting torque from the brushless motor is the number that matters on this grass, because torque is what keeps the blade turning when a wet stolon mat loads up under the deck, and it is well clear of what the gas units in this list produce.
The height lever runs from 1.25 to 4 inches, so a Floratam lawn can be held at the top of the recommended range without any modification. Touch Drive self-propulsion engages with palm pressure and the speed dial sits under your fingers, which means you can slow down in the thick patches along an irrigation line without hunting for a lever.
The Select Cut system is the part I did not expect to care about. Swapping the lower blade lets you switch between mulching, high-lift bagging and an extended runtime setup, and on a humid lawn where St. Augustine clumps easily, moving to the high-lift blade for a bagging pass is a real improvement rather than a gimmick.
Owners report 4.3 stars across more than 1600 reviews, with the bulk praising cutting power and self-propelled control. The recurring complaint is runtime: a single 7.5Ah pack gives up to 60 minutes, and Florida homeowners mowing twice a week on larger lots tend to buy a second battery rather than plan a charge break.
What to check before you buy the LM2135SP
Confirm your lawn is under roughly half an acre, or plan on a second 7.5Ah pack. On a half-acre lot in peak season, one charge is usually enough for a mow at the 4 inch setting, but only just.
If you already own EGO 56V ARC tools, the platform compatibility makes this an easy decision. If you do not, the kit includes the battery and rapid charger, which is why it doubles as an entry point to the ecosystem.
Where it falls short
The plastic-and-metal construction saves weight at 55.3 pounds, which is genuinely easy to lift, but it is less rigid under a side load than the all-steel decks in the gas group. On very uneven ground with a heavy thatch layer you can feel the flex.
There is no bag-full sensor and no side-discharge-only mode listed, so the mulch and bag options are the two workflows you have. For most St. Augustine lawns that is enough, but anyone who wants a clean rear-discharge edge will need a different deck.
2. PowerSmart 22-Inch 150cc Self-Propelled Gas Mower
- USA-made Briggs and Stratton EX625 engine with ReadyStart
- Rear-wheel drive gives traction on inclines and rough ground
- Single-lever 6-position height adjustment
- 3-in-1 mulching with a 1.4 bushel bag
- 150cc is the smallest engine here and can bog in very tall growth
- 3.9 inch maximum stops just short of a full 4 inch cut
The PowerSmart is the gas answer for anyone who wants a steel deck and a Briggs engine without moving up to a commercial machine. The 22-inch steel deck is the right size for a typical Florida lot, and the EX625 with ReadyStart means no carburetture tinkering on a humid Saturday morning.
Rear-wheel drive is the detail that matters here. Florida yards are rarely flat, and rear-wheel traction on a heavy steel deck is what keeps the mower from bogging on a slope or cutting unevenly across a crown in the middle of the lawn.
The 3-in-1 setup covers mulching, rear discharge and bagging with a 1.4 bushel bag, and the single-lever six-position adjustment moves the whole deck at once. That is a 1.5 to 3.9 inch range, which is worth flagging: it clears a Palmetto or Cobalt lawn at 3.5 inches without trouble, but it is a quarter inch short of the 4 inches a Floratam lawn ideally wants.
Rating is 4.0 across more than 1000 reviews, with the value and the steel deck drawing most of the praise. The most common complaint is exactly the one this grass provokes: a 150cc engine will bog in neglected, overgrown St. Augustine, so this mower suits a lawn that gets mowed regularly rather than one being recovered.
What to check before you buy the PowerSmart
Measure your lawn first. This is a 22-inch walk-behind with a 1.4 bushel bag, which works out to a comfortable mow for most lots up to about half an acre with a couple of bag empties.
Ask yourself honestly whether you will mow twice a week through July. If you will, the 150cc engine is fine. If you plan to cut a neglected lawn back from six inches, buy more displacement.
Where it falls short
That 3.9 inch ceiling is the honest limitation. It is not a dealbreaker on most St. Augustine varieties, but on a Floratam lawn in coastal Florida, running consistently a quarter inch low is exactly the habit that leads to scalped stolons and brown patch later in the season.
At 72 pounds it is not a light lift, and the fixed-speed drive gives you no in-pass pacing control when the canopy is heavy. Owners who want to crawl through a thick patch without stalling will miss a CVT.
3. Greenworks 80V 21-Inch Cordless Self-Propelled Mower
- 80V brushless drivetrain delivers high torque for dense warm-season turf
- Steel deck rather than plastic
- Rear-wheel drive with variable speed control
- Runs about three times quieter than gas
- 4-year warranty and 75+ compatible 80V tools
- Single 4.0Ah pack limits continuous runtime
- 75 pounds makes it one of the heavier mowers here
This mower shares the highest rating in the group at 4.4 stars, and the reason is simple: 80 volts of brushless drivetrain driving a 21-inch steel deck. That combination is exactly the spec profile St. Augustine rewards, since thick coarse turf needs torque and thick turf needs a rigid deck.
Rear-wheel drive with variable speed control handles the slope-and-crown problem better than most walk-behinds at this size. You can dial the pace down as the canopy thickens without disengaging the drive, which is how you avoid the stall-and-restart pattern that chews up thick turf.
The included 4.0Ah battery is rated for up to half an acre per charge depending on grass condition and technique. On a Floratam lawn cut at 4 inches in peak season, assume you are near the limit of that figure, so plan the route so the mower finishes near the dock area rather than the far corner.
Owners consistently highlight the power-to-noise ratio, the steel deck, and cross-compatibility with more than 75 other 80V tools. Runtime is the trade-off they name most often, which is the same trade-off the whole cordless category has.
What to check before you buy the Greenworks 80V
Decide if you want one platform for the whole yard. The 80V system covers blowers, trimmers, chainsaws and hedge tools, and the 4-year limited tool and battery warranty is among the longer ones in this roundup.
Check the height adjustment range on the exact model in front of you, because Greenworks changes deck designs between model numbers. Confirm the top notch clears 4 inches before you commit, and confirm which platform you want, since 60V and 80V batteries are not interchangeable.
Where it falls short
A single 4.0Ah pack is roughly half the capacity of a dual-battery kit, so anyone mowing more than half an acre should budget for a second pack or a faster charger. On an acre lot, that is a real interruption twice a week in summer.
At 75 pounds it is one of the heavier self-propelled mowers here despite being battery powered. On a mower this size, the battery and the steel deck together are why.
4. Greenworks 60V 21-Inch Dual-Battery Self-Propelled Mower
Greenworks 60V 21in Self-Propelled Lawn Mower, (2) 4.0 Ah Battery Kit
- Dual battery kit covers up to three quarter acre per charge
- Rear-wheel drive built for thick grass and slopes
- 4-in-1 including turbo leaf pickup
- Instant start with no maintenance
- 4-year warranty across 75+ 60V tools
- Less torque headroom than the 80V Greenworks
- Plastic body flexes more than a steel deck
If your St. Augustine lawn is a half acre or larger, the two included 4.0Ah batteries are the reason this one earns its place. The manufacturer rates it for up to three quarter acre per charge depending on terrain and technique, which on a Florida lot in July is a genuine single-session mow rather than a promise.
Greenworks describes the rear-wheel drive as designed for slopes and thick grass specifically, and that is the design target most relevant here. The drive is on at a single speed with on-the-go variable control, so you can adjust as you go without stopping.
The height lever covers 1 to 4 inches across seven positions, which is the widest stated range in the group and comfortably handles a Floratam lawn at the top notch. The 4-in-1 configuration adds side discharge and a turbo leaf pickup mode, useful in a coastal yard where palms drop a constant litter of fronds.
Reviewers rate it 4.4 across 619 reviews with 73 percent five-star, and the two-battery format is the dominant positive in the feedback. The complaints are narrow: the torque ceiling is lower than the 80V model, and the plastic construction flexes more than a steel deck would.
What to check before you buy the 60V kit
Confirm you want the 60V platform rather than 80V. Both cover a wide tool range, but they are not cross-compatible, and picking the wrong one locks you out of the batteries you buy later.
Two batteries also means you need a place to charge both. If your garage shelf space is tight, the two-pack dock arrangement is worth thinking about before delivery.
Where it falls short
Torque headroom is the honest limit. In tall, wet, neglected growth the 60V platform has less reserve than the 80V, and owners who let a lawn get away from them report the motor working harder for the same cut.
The plastic body is lighter in transit but less rigid, so on uneven ground the deck can move a little under load. For a manicured lawn mowed on schedule that is a non-issue. For heavy thatch it is noticeable.
5. SENIX 22-Inch 201cc Self-Propelled Gas Mower
SENIX 22Inch 201cc 3-in-1 Gas Lawn Mower, Rear Wheel Self-Propelled Mower
- 201cc OHV engine with 8.8 ft-lb of torque
- Manganese steel blades at 45-50 HRC hold an edge
- Vortex tunnel airflow improves bagging and discharge
- Central six-position height adjustment to 4 inches
- Single-speed drive gives no variable pacing
- Two-year warranty is the shortest here
The SENIX is the gas mower here with the most torque relative to its displacement, and 8.8 ft-lb from a 201cc OHV four-cycle is a meaningful margin when the lawn is soaked. Torque headroom, not headline horsepower, is what keeps a rotary deck from bogging in thick St. Augustine.
The blade specification is what drew my attention for this grass specifically. Manganese steel alloy blades rated at 45 to 50 HRC are harder than a typical stamped steel blade, and a harder edge holds its sharpness longer against the abrasive fibre of wide St. Augustine blades.
The vortex tunnel airflow design routes air through the deck so clippings move into the chute or bag instead of packing against the deck walls, which is the single biggest cause of clogging when you mow damp turf. Central six-position height adjustment gives a 1.25 to 4 inch range from one lever.
It holds a 4.2 average across 423 reviews with 73 percent five-star, and reviewers single out raw engine torque, blade durability and deck strength. The fixed drive speed is the trade-off that shows up most, along with some longer-term build consistency complaints.
What to check before you buy the SENIX
The 22-inch deck is listed for lawns up to about 2200 square meters, so it is a comfortable fit for a typical Florida lot and a stretch beyond that. Larger properties should look at a wider deck or a second machine.
Buy a spare blade while you are at it. With 45 to 50 HRC manganese steel, a spare is more useful here than on a mower with a mild stamped blade, because the edge is what determines cut quality on this grass.
Where it falls short
Single-speed self-propulsion at up to 2.9 MPH means no in-pass pacing. If a patch is extra thick, your only options are to change direction or lift the bail bar, and neither is as smooth as a CVT.
The foldable handle is a genuine bonus for garage space, but the two-year warranty is the shortest in this roundup, and for a machine expected to survive Florida humidity for a decade that is worth weighing.
6. YARDMAX 22-Inch 201cc CVT Self-Propelled Mower
YARDMAX 22 in. 201cc Select PACE 6 Speed CVT High Wheel FWD 3-in-1 Gas Walk Behind Self Propelled Lawn Mower, Black (YG2860)
- Only mower here with a 6-speed CVT so drive pace tracks your walking speed
- High-wheel front-wheel drive with spiked tires rolls over uneven ground
- Automatic choke means no priming
- Deck cleanout port for fast underside cleaning
- Five-year spare part availability
- Heavy at 84.9 pounds
- which makes it awkward to turn at the edges
- Highest share of one-star reviews among the gas mowers
The YARDMAX solves a problem none of the other walk-behinds here solve, and on a typical Florida yard that problem is the ground. The high-wheel front-wheel drive and the aggressive spiked rubber tread pattern are designed to roll over uneven terrain rather than fight it, and unevenness is the normal condition of a lot with sandy patches and irrigation domes.
The 6-speed CVT is the other differentiator. Instead of a single fixed speed, the drive pace tracks your walking speed, so you can slow right down entering a thick patch of 4 inch Floratam without disengaging self-propel and without the blade bogging.
The automatic choke removes the priming ritual that makes gas mowers miserable to start in humid weather, and the deck cleanout port is a small detail that saves real time because St. Augustine clippings mat against the deck underside quickly. Single-lever height adjustment and 3-in-1 mulching, bagging and side discharge round out the package.
It scores 4.0 across 419 reviews. The CVT speed control and the traction get repeated praise, while a larger-than-average group of one-star reviews reports starting and durability problems.
What to check before you buy the YARDMAX
Confirm the published height range for the specific model, because the deck on this YARDMAX is a stamped steel design with a single-lever adjustment and the range is not the same as the 4 inch decks elsewhere in this list. Verify the top notch against a ruler on the machine itself.
Think about storage and transport. It is heavier than every other mower in the roundup except the BILT HARD, and getting it into a vehicle is a two-person job for most people.
Where it falls short
Weight is the practical problem. The heavy wheels and high-wheel chassis that make it so stable over rough ground also make it awkward to turn at the edges of a bed or lift over a kerb.
That 17 percent one-star share is the highest among the gas mowers here, and the reports cluster around starting and long-term durability. If you have a dealer network nearby that is a real consideration; if you do not, that risk is harder to manage.
7. WORX WG760 40V Cordless Self-Propelled Mower
Worx Cordless Lawn Mower, 40V 21″ 3-in-1 Grass Mower for 1/2 Acre, WG760
- IntelliCut sensors raise cutting speed in thick grass automatically
- Two 5.0Ah batteries usually cover a half-acre lot with charge to spare
- Quiet enough for early morning mowing in summer heat
- Mulches without visible clumps
- Lightweight at 63.1 pounds
- Drive speed control is a handle lever rather than a progressive thumb control
- Replacement blades only through Worx customer support
The AeroDeck is the feature that matters most for this grass, and it is the reason I would choose this mower for a coastal yard. The vented deck design raises air volume through the deck to prevent the clogging and clumping that happens the moment you mow damp St. Augustine.
IntelliCut sensors are the other part worth understanding. They automatically increase cutting speed where the grass is thick and back it off where the lawn is sparse, which on a St. Augustine lawn with irregular density means fewer stalls and a more even cut without you riding the controls.
Two included 20V 5.0Ah PowerShare Pro batteries typically cover a half-acre lot with charge remaining, and the 7-position lever gives a 1.5 to 4 inch range. At 63.1 pounds with a fully collapsible handle, it is also the easiest machine here to move from the shed to the lawn and to store upright.
Owners with thick lawns report it plows through heavy growth quietly, and the 4.4 average across 350 reviews comes with 71 percent five-star. The most-cited gripe is the non-progressive self-propel speed lever, and some batteries need a couple of charge cycles before reaching full rated capacity.
What to check before you buy the WG760
Do you want the 140-plus product PowerShare battery range, or the 56V class that the EGO kits use? The 40V platform is a large tool ecosystem, but it is a separate one, so decide which yard tools you will eventually buy before you commit.
Check the drive control habit. If you prefer to modulate speed continuously with a thumb dial while you walk, this lever arrangement will frustrate you, and the LM2135SP is the better fit.
Where it falls short
Blade replacement through customer support alone is a genuine inconvenience on a mower whose cut quality depends so heavily on a sharp edge. Plan a sharpening kit rather than relying on replacements.
Two or three initial charge cycles before full rated capacity is a real onboarding wrinkle. If you mow early on a brand new pack, do not judge the runtime by the first pass.
8. EGO POWER+ LM2114SP Lightweight Cordless Mower
EGO POWER+ 21″ Cordless Electric Lawn Mower Kit, Self-Propelled – LM2114SP
- 6.0 ft-lbs of cutting torque with no emissions
- Dual-toggle handles engage self-propel with either hand
- Lightest self-propelled unit here at 50.9 pounds
- 7-position height adjustment reaching 4 inches
- Push-button start with LED headlights
- Single 6.0Ah battery gives about 50 minutes per charge
- Plastic construction is lighter but less rigid than steel
The LM2114SP is the same EGO approach as the LM2135SP with a smaller battery, and for a quarter-acre to third-acre lawn that is the better-balanced machine. At 50.9 pounds it is the lightest self-propelled mower in this roundup by a wide margin, and that weight shows every time you lift it into a vehicle or manoeuvre around a bed.
Torque is still the headline: 6.0 ft-lbs from a brushless motor, which is enough headroom for a tall Floratam canopy at the 4 inch setting. The 7-position height lever runs 1.25 to 4 inches, so it clears the same height requirement as the bigger kit.
The dual-toggle handleset lets you engage self-propel with either hand, which is genuinely useful when you are turning at the end of a pass and want to keep one hand on the bail bar. Push-button start and LED headlights make early and late mowing practical, which matters in summer when the only comfortable window is before nine.
It holds a 4.4 average across 351 reviews with 75 percent five-star, the most favourable distribution among the cordless mowers here. Runtime is the constraint owners name: about 50 minutes on the included 6.0Ah pack, less than the LM2135SP kit.
What to check before you buy the LM2114SP
Measure the lawn honestly. On a third of an acre at 4 inches, one charge is workable. Past half an acre you will be swapping packs mid-mow, and at that point the LM2135SP is the better purchase.
If you already run EGO 56V ARC tools, the 6.0Ah pack slots straight into that system, so the decision is really about capacity rather than platform.
Where it falls short
The plastic construction is what buys the low weight, and it is less rigid under load than the steel decks in the gas group. On a lawn with heavy thatch and uneven ground, you can feel the deck move.
About 50 minutes of runtime is the shortest of the EGO options here, and that becomes an annoyance quickly if your mowing day lands on a hot afternoon rather than a cool morning.
9. Segway Navimow i105N Wire-Free Robot Mower
- No perimeter wire to trench across the lawn
- RTK+Vision holds centimetre-level accuracy under trees
- 58 dB(A) is quiet enough to run at night
- App scheduling and multi-zone management built in
- Consistent parallel lines with automatic re-coverage
- Height tops out at 3.6 inches
- Factory wheels have limited traction in thick grass
- Does not mulch and edges still need a string trimmer
The Navimow i105N is the only robotic mower here, and the wire-free setup is the feature that matters for this grass. St. Augustine spreads by stolons that run across the surface, and a boundary wire means either trenching through them or stapling over them. A virtual boundary mapped from your phone avoids the problem entirely.
RTK+Vision positioning with the enhanced EFLS 2.0 module holds centimetre-level accuracy under tree cover and in narrow corridors, which is where cheaper robot mowers wander. The 140-degree camera with AI detection of more than 150 obstacle types handles the dogs, the toys and the garden hose that a warm-season Florida lawn inevitably collects.
At 58 dB(A) it is quiet enough to run while the household sleeps, which in a coastal neighbourhood with close setbacks is a real advantage. Multi-zone management supports up to 12 zones with separate schedules and mowing directions, and the planned pattern changes direction after full coverage to avoid visible wheel tracks.
It rates 4.1 across 391 reviews. Owners love the wire-free setup, the quietness and the cut quality once mapping is done properly. The recurring complaints are traction on the factory wheels, occasional map loss, and the fact that it does not mulch.
What to check before you buy the Navimow i105N
Confirm the lawn size. This model is listed for up to 0.125 acre, so a typical Florida lot needs something larger. The 3-year full warranty is solid, and the optional 4G module adds theft tracking that matters for an unattended machine.
Check your sky view. GNSS-based positioning needs a clear view of the sky for the antenna, and on a lot hemmed in by large trees the dock placement becomes a genuine constraint.
Where it falls short
The 3.6 inch maximum height is the dealbreaker for a Floratam lawn. That is fine on Palmetto, Raleigh or Cobalt, but on the most common Florida variety you will be cutting below the recommended range, which is precisely the habit that stresses stolons and invites brown patch.
It is a maintenance mower, not a recovery cutter, and the stock wheels have limited traction in thick grass, so many owners upgrade to off-road tires. Clippings also sit on the surface rather than being mulched, and edges still need a separate string trimmer.
10. BILT HARD 21-Inch 201cc Self-Propelled Gas Mower
- 9.0 ft-lb of torque from a 201cc OHV engine
- No-choke and no-primer starting
- Single lever syncs all four wheels
- 3-in-1 steel deck with mulching side discharge and bagging
- Foam-wrapped angled handle reduces hand fatigue
- 3.75 inch maximum falls short of the 4 inch target
- Heaviest machine in the roundup
- Thinnest review base at 111 ratings
The BILT HARD is the most compact option here, and the 9.0 ft-lb of torque from a 201cc OHV four-cycle is the highest torque figure among the gas units in the roundup. That headroom matters on St. Augustine because it is what stops the blade bogging when the canopy is long and damp.
Two convenience details stand out. The no-choke, no-primer design starts without any manual adjustment, which owners repeatedly single out, and the single lever synchronises height adjustment across all four wheels rather than moving one side at a time.
The 3-in-1 steel deck handles mulching, side discharge and rear bagging, and the foam-wrapped angled handle reduces hand fatigue on a long pass. Rear-wheel drive single-speed self-propulsion handles a moderate slope, though it gives you no in-pass pacing control.
It holds a 4.3 average, but across only 111 reviews, which is the thinnest feedback base in the group. Most owners call it easy to assemble, quick to start and well suited to small-to-medium yards, with isolated reports of wiring-related starting failures.
What to check before you buy the BILT HARD
Measure your lawn. A 21-inch deck with rear bagging suits a small-to-medium yard, and going much past that means a lot of walking with a heavy machine. Confirm your lot size before assuming it will cover a Florida property comfortably.
Keep the battery-and-charger thinking in the other column. This is a gas mower, so your fuel and storage footprint is real, and it is worth comparing against a cordless kit if you already own batteries.
Where it falls short
The 3.75 inch maximum is the clearest limitation. On a Floratam lawn that is a quarter inch under the target, and it is a shortfall you cannot engineer around with a lever adjustment.
At 89.2 pounds with fixed single-speed drive, it is the heaviest machine here. The thin 111-review base also means you are buying on less long-term evidence than the other nine.
How to Choose a Lawn Mower for St. Augustine Grass?
The top of the height range decides more than any other specification. Check that published maximum first, because a mower that stops at 3 inches is simply wrong for this grass, and several that reach only 3.6 to 3.9 inches will run a Floratam lawn low. Mowers that clear 4 inches include the LM2135SP, the Greenworks 60V kit, the SENIX, the WORX WG760 and the LM2114SP.
Blades: wavy, high-lift and mulching
St. Augustine’s wide flat blades tear rather than slice when dull, which is why cut quality here tracks blade sharpness more than deck size. A high-lift blade is designed to pick thick turf up into the cutting path instead of pushing it along, and that is the geometry you want on a dense stolon mat.
The most specific blade advice in the whole search comes from a long-running LawnSite thread on mower setup in Florida, where a landscaping operator reported running wavy blades with a mulch kit on a zero-turn machine and handling thick St. Augustine well, provided you double cut when the lawn has been neglected. The same thread is where the double-cut technique comes from: mow at 4 inches, then cross the same path again at 4 inches to tidy up the strip.
Whichever blade you run, treat the 20 to 25 hour interval as a schedule rather than a reaction. A blunt blade on this grass shows up as a lawn that browns off a few days after mowing, and owners often blame the mower when the real cause is the edge.
Mulch, bag or side discharge in humid conditions
On a high-humidity St. Augustine lawn, mulching only works with a genuine mulching blade and a clean deck. If clippings are long enough to mat, they sit on the canopy, block light and can smother the lawn rather than feed it. Bagging or side discharge is the safer choice after a wet morning or when thatch has built up.
Side discharge is the fastest option on a large open lot because there is no bag to empty, but it needs an edge discipline you do not get for free. Bagging gives the cleanest cut and the biggest reduction in thatch, at the cost of stopping every few passes. Most owners in Florida settle on bagging for the tall-growth weeks and mulching for the rest.
Sizing cordless batteries for a half acre to an acre
Do the arithmetic on lawn area rather than trusting a marketing figure. The Greenworks 60V dual-battery kit is rated for up to three quarter acre per charge, the Greenworks 80V covers up to half an acre, and the EGO LM2135SP gives up to 60 minutes on its 7.5Ah pack. For a full acre of Floratam cut at 4 inches in peak season, plan on two battery sets, not one.
Heat works against you. Battery runtime drops in high ambient temperatures, and peak St. Augustine season in Florida is exactly when the lawn is thickest and the air is hottest. Mowing early in the morning gives you both the cool air and the stiffest grass.
What to do when your mower stops at 3 inches
First, confirm the true height with a ruler at the blade tip rather than trusting the lever position, because deck geometry varies a lot between models. If the measurement really is under 4 inches, the fix is mechanical: taller deck wheels, a deck spacer, or a replacement deck with a taller frame.
Before spending money on parts, check whether your variety actually needs 4 inches. Palmetto, Raleigh and Cobalt are commonly maintained closer to 3.5 inches, and a mower that tops out at 3.75 inches handles those perfectly well. A mower that stops at 3 inches has no workaround and is the wrong purchase.
Gas, cordless or robot, by lawn size
Under a quarter acre, a cordless walk-behind handles everything on this list and the running costs drop to almost nothing. Quarter to half an acre, a dual-battery cordless kit or a 21 to 22 inch gas mower is the sweet spot. Half an acre to an acre, gas gains the edge on uninterrupted runtime, and a stand-on or zero-turn becomes worth a look for anyone mowing that much twice a week.
A robot mower suits owners who value their Saturday mornings more than their cutting height control, and the Navimow’s 3.6 inch ceiling makes it a fit for the shorter varieties rather than Floratam. Our guide to robot lawn mowers under 1000 covers the larger robot classes if your lot is bigger than an eighth of an acre.
Frequently Asked Questions
What is the best mower to use on St. Augustine grass?
A high-powered rotary or robotic mower with a deck that reaches at least 4 inches is the best choice for St. Augustine grass. The wide, coarse blades need torque to keep the deck moving in wet growth and a high-lift or mulching blade to lift the turf into the cut. Keep the blade sharp on a 20 to 25 hour schedule and mow every five to seven days in season.
What is the recommended lawn mower height for St. Augustine grass?
Mow St. Augustine at 3.5 to 4 inches and never below 3 inches. That height shades the crown and stolon roots, holds moisture through the afternoon and blocks the light weeds and brown patch need. Floratam is usually run near 4 inches, while Palmetto, Raleigh and Cobalt hold up fine closer to 3.5 inches. Never remove more than a third of the blade in one pass.
Can you mow St. Augustine grass with a reel mower?
No. Reel mowers use a scissors action that needs thin, fine, upright blades, and St. Augustine has coarse, flat, wide blades that fold over and spring back instead of standing into the reel. The lawn gets pushed down rather than cut, the stolons that run across the surface resist the cut, and wet clumps make the problem worse. A rotary or robotic deck is the only realistic option.
Can electric lawn mowers cut thick grass?
Yes, when the voltage platform and torque figure support it. The EGO kits in this roundup deliver 6.0 to 7.0 ft-lbs of cutting torque, which is more than several of the gas units listed here, and the 80V Greenworks carries a steel deck rated for dense warm-season turf. The limit is runtime rather than cutting ability, so check battery capacity against your lawn size before buying a single-pack kit.
Do robot mowers work on St. Augustine grass?
Some do and some are explicitly not rated for it, so check the height ceiling first. The Segway Navimow i105N adjusts from 1.6 to 3.6 inches, which suits Palmetto and Cobalt but runs low on Floratam. Its wire-free virtual boundary is a real advantage because stolons are never trenched. Factory wheels have limited traction in thick turf, so off-road tires are a common upgrade.
The Best Lawn Mowers for St. Augustine Grass in 2026
The EGO POWER+ LM2135SP is the pick: 7.0 ft-lbs of torque, a 1.25 to 4 inch height range and 60 minutes on a 7.5Ah battery, all of which check every box St. Augustine sets. The Greenworks 80V is the alternative if you want the steel deck and the highest rating in the roundup, and the Greenworks 60V dual-battery kit is the one for lots past half an acre.
On gas, the SENIX leads on torque, blade hardness and a genuine 4 inch ceiling, while the PowerSmart is the value route if 3.9 inches is enough for your variety. The Navimow handles the mowing for you if a 3.6 inch ceiling suits your grass and you would rather not spend Saturday morning outside.
Whichever you pick, run the deck high, sharpen the blade every 20 to 25 hours, and never cut below 3 inches. That habit matters more than the machine. For more options, see our Toro lawn mower reviews and Husqvarna robot mower guide before you settle on a brand ecosystem.