Dollar weed thrives where you least want it — in moist, shaded patches of an otherwise solid lawn. Its creeping root system spreads fast, and most all-purpose sprays bounce right off its waxy leaves, leaving you stuck pulling runners by hand. Finding a targeted solution that penetrates that defense and kills the stolon network without torching your turfgrass is the real challenge here.
I’m Mohammad Maruf — the founder and writer behind Gardening Beyond. I’ve spent years studying the chemical profile of selective and non-selective herbicides, cross-referencing active ingredient efficacy against broadleaf perennial weeds, and filtering through thousands of aggregated owner experiences to isolate what actually works on persistent lawn invaders like dollar weed.
After comparing formulation types, coverage rates, and the chemical compounds proven to penetrate waxy cuticles, this guide narrows down the top performers so you can confidently choose the best weed killer for dollar weed without second-guessing the label.
How To Choose The Best Weed Killer For Dollar Weed
Dollar weed (Hydrocotyle umbellata) is a perennial broadleaf weed with thick, waxy leaves that deflect water-based sprays. A generic all-purpose herbicide often beads up and rolls off, leaving the stolon network intact. You need a product that either penetrates that wax layer or is formulated with an active ingredient the plant absorbs systemically. The factors below determine whether your application works or the weed bounces back within two weeks.
Active ingredient targeting
Atrazine is the gold standard for dollar weed suppression in St. Augustine and centipede lawns because it disrupts photosynthesis in broadleaf weeds while leaving the turf relatively unharmed. For warm-season grasses, atrazine-based formulas (like Southern Ag Atrazine) deliver season-long control when applied in early spring. In cooler-season turf or for spot treatment of small patches, a triclopyr/diquat combination (found in the latest Roundup formulations) penetrates waxy cuticles faster and kills the root system within days — but these are non-selective, so you must avoid contact with desirable grass.
Selective vs. non-selective
If dollar weed is scattered through your main lawn, you need a selective herbicide — one that kills broadleaf weeds without damaging the turfgrass species you’ve planted. Ortho WeedClear, for example, uses a selective formula safe for fescue, bermudagrass, zoysiagrass, and Kentucky bluegrass. If the infestation is isolated to a driveway crack, a mulched bed, or a bare patch where you plan to re-sod, a non-selective systemic like glyphosate (41% concentrate in Eraser) gives a total kill that prevents regrowth from the root fragments.
Application format and coverage
Ready-to-use (RTU) bottles with a comfort wand or foam-tip trigger make spot treatment easy for small lawns and for targeting individual dollar weed clumps. For larger properties (over 5,000 sq ft), a concentrate that you mix with water in a gallon sprayer is more economical and allows you to dial in the concentration. Pay attention to the coverage figure on the label: a 1-gallon RTU covering 20,000 sq ft offers far better value per square foot than a 30-ounce trigger bottle that covers only 3,000 sq ft.
Rainfastness and drying time
Dollar weed often grows in damp, low-lying areas that stay wet longer. A rainfast window of 10 minutes (like the foam-based Roundup) means you can apply right before a light drizzle without losing effectiveness. Older formulas may require 2 to 6 hours of dry time after application, which is impractical in humid climates or during rainy seasons. Always check the label for the minimum dry time before irrigation or rainfall.
Quick Comparison
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| Model | Category | Best For | Key Spec | Amazon |
|---|---|---|---|---|
| Southern Ag Atrazine | Selective | St. Augustine & Centipede lawns | 1 gallon, atrazine 4% | Amazon |
| Ortho WeedClear | Selective | Spot treatment on cool-season turf | 1 gal RTU, battery wand | Amazon |
| Bonide Deadweed Brew | Non-selective | Organic beds & fence lines | 128 oz RTU, organic approved | Amazon |
| Control Solutions Eraser | Non-selective | Large-area total kill | 32 oz concentrate, 41% glyphosate | Amazon |
| Roundup Weed & Grass III | Non-selective | Quick visual results on waxy leaves | 30 oz trigger, triclopyr/diquat | Amazon |
In‑Depth Reviews
1. Southern Ag Atrazine St. Augustine Grass Weed Killer, 1 Gallon
This 1-gallon jug of atrazine concentrate is the closest thing to a prescription for dollar weed in St. Augustine and centipede lawns. Atrazine disrupts photosynthesis specifically in broadleaf weeds while leaving warm-season turfgrasses largely unaffected — a selectivity advantage that few other herbicides offer. The label lists dollar weed as a primary target, and the pre-emergent residual activity also prevents new seeds from germinating for several weeks after application.
Mix rate is straightforward: 4 fluid ounces per gallon of water for established dollar weed, applied with a pump sprayer when temperatures stay below 85°F. Users consistently report visible wilting within five days and complete browning of the stolon network after a single treatment in early spring. The concentrate format yields roughly 32 gallons of mixed spray, covering a 500 sq ft area per gallon — enough for multiple applications across a typical residential lawn.
One limitation is that atrazine is not safe on bermudagrass, fescue, or ryegrass, so you must confirm your turf type before spraying. It also requires a 24-hour dry period to activate fully. Inside the green space, this product is the most cost-effective, lawn-safe weapon against dollar weed known to work.
What works
- Selective atrazine formula spares St. Augustine and centipede grass
- Pre-emergent residual stops dollar weed seeds from sprouting
- High concentrate value — one jug treats the whole season
What doesn’t
- Not safe on bermudagrass, fescue, or cool-season turf
- Requires 24 hours dry time before rain or irrigation
2. Ortho WeedClear Lawn Weed Killer Ready-to-Use with Comfort Wand, 1 gal.
Ortho WeedClear is a ready-to-use selective herbicide that comes with a battery-powered Comfort Wand, eliminating the need for a separate sprayer and reducing the risk of over-spray on nearby turf. The formula targets broadleaf weeds including dollar weed, crabgrass, dandelion, and clover while leaving bermudagrass, fescue, Kentucky bluegrass, ryegrass, and zoysiagrass unharmed when applied as directed. The wand’s built-in battery pump delivers a consistent spray pattern that covers the leaf surface evenly — critical for dollar weed’s waxy leaves that require full coverage to absorb the active ingredient.
The 1-gallon container covers up to 20,480 sq ft, which is generous for a ready-to-use product. Results appear within 7 to 10 days on dollar weed, with the stem and root system yellowing and collapsing after one application. The product is best applied in spring or fall when dollar weed is actively growing and soil temperatures are above 60°F. Because it is selective, you can spot-spray among desirable grass without creating dead patches.
On the downside, the foam tip on the wand can clog if you let the product sit for weeks between uses. The battery also requires periodic replacement (one AA battery). For homeowners who want a true grab-and-go solution that doesn’t require mixing or sprayer calibration, this kit saves time and guesswork.
What works
- Selective formula safe on multiple cool/warm-season turf types
- Battery wand simplifies spot treatment and reduces drift
- Covers 20,000+ sq ft from one bottle
What doesn’t
- Wand tip may clog if not rinsed after use
- Requires battery replacement for the wand pump
3. Control Solutions 82004318 Eraser & Grass Killer Concentrate, 1 Quart
Eraser Concentrate packs 41% glyphosate — the highest concentration you’ll find in a consumer-grade non-selective herbicide. For dollar weed growing in mulched beds, along fence lines, or in gravel areas where no turf protection is needed, this concentrate delivers a total systemic kill that penetrates the leaf cuticle and translocates down to the root nodes. Because it has no residual soil activity, you can plant new grass or ornamentals within days once the treated area dries.
The quart (32 oz) concentrate mixes at a rate of 3 to 6 ounces per gallon of water depending on weed maturity. A single quart produces up to 10 gallons of mixed spray, covering roughly 5,000 sq ft at standard application rates. The low-odor, water-based formula is rainproof within 2 hours, making it practical for morning applications in humid climates. Users report complete browning of dollar weed within 7 to 14 days, with no regrowth from the stolons.
The biggest caution is overspray drift — glyphosate kills any green plant it touches, so you must shield desirable grass and ornamentals with cardboard or plastic during application. It also lacks the foam marker that makes spot treatment easier. If you need to clear a large infested bed before re-landscaping, this concentrate gives you the highest kill ratio per dollar.
What works
- 41% glyphosate — highest consumer concentration for total kill
- No soil residue, safe for replanting after drying
- Excellent value per square foot as a concentrate
What doesn’t
- Non-selective — kills any grass it touches
- No built-in marker dye or foam to track coverage
4. Roundup 5003410 Weed and Grass Killer III Ready-to-Use Trigger Spray, 30-Ounce
This Roundup variant uses triclopyr and diquat rather than the classic glyphosate formula — a critical detail because triclopyr penetrates waxy leaf surfaces much more effectively, making it an ideal match for dollar weed. The foam-on-spray technology coats the leaf with visible white foam so you can see exactly where you’ve applied, reducing the risk of overspray onto desirable plants. Visible results begin within 6 hours, with complete plant death (including the root system) in about a week.
The 30-ounce trigger spray bottle covers roughly 3,000 sq ft, which limits it to spot treatment or small infestations. Rainproof in just 10 minutes, this product works well even if a shower rolls in shortly after you spray. The low item weight (0.01 oz bottle weight) makes the package feel misleadingly small, but the foam action ensures the active ingredient stays on the leaf rather than dripping off — a real advantage on dollar weed’s glossy foliage.
Owners note that tougher perennial weeds like dandelions may require a second application after one week. The triclopyr/diquat mix is non-selective, so you cannot use it on lawn turf without killing the grass. For driveway cracks, patio edges, and mulched beds where you want fast visual feedback, the foam system is hard to beat.
What works
- Foam spray sticks to waxy dollar weed leaves without runoff
- Visible results in 6 hours, root kill in 7 days
- Rainproof in 10 minutes — practical for damp climates
What doesn’t
- Non-selective — cannot be used on lawn turf
- Small bottle covers only ~3,000 sq ft
5. Bonide Captain Jack’s Deadweed Brew, 128 oz Ready-to-Use
Bonide Captain Jack’s Deadweed Brew is a ready-to-use non-selective herbicide that carries OMRI certification for organic gardening. Its natural-derived formula targets both broadleaf and grassy weeds, and unlike most organic sprays, it remains effective in temperatures as low as 40°F. The 128-ounce bottle covers a generous area without requiring any mixing — just attach the nozzle and spray. Once dry, the residue becomes waterproof, preventing rain from washing it off the leaf surface.
On dollar weed, the formula works by dessicating the leaf tissue, causing visible burn within hours. Because it is a contact killer rather than a systemic one, you need thorough coverage of every leaf and stolon to prevent regrowth from untreated root fragments. The product works best on young, actively growing dollar weed in spring; mature clumps with thick root networks may require a second application after 7 to 10 days. It is ideal for organic garden beds, around mature trees, along fence lines, and in greenhouses where chemical residues are a concern.
The main trade-off is that it is non-selective and will damage or kill any ornamental plant it contacts. It also lacks residual soil activity, so new weed seeds can germinate in treated areas after a few weeks. For organic gardeners who need a fast-acting, no-mix solution for dollar weed in non-lawn areas, this is the cleanest option available.
What works
- OMRI certified for organic gardening
- Works at low temperatures (40°F) for early/late season use
- Rainproof once dry; no mixing required
What doesn’t
- Contact killer — requires thorough leaf coverage for full root kill
- Non-selective; damages any plant it touches
Hardware & Specs Guide
Active Ingredient Penetration
The single most important factor when selecting a dollar weed killer is whether the active ingredient can penetrate the weed’s waxy leaf cuticle. Atrazine works through foliar absorption and root uptake, making it effective as both a contact and systemic treatment in warm-season grasses. Triclopyr (found in Roundup III) is specifically formulated to break through waxy surfaces and is often used in brush killers for the same reason. Glyphosate (41% concentrate) systemically translocates to the root nodes but requires a surfactant to stick to glossy leaves — most concentrates already include one, but ready-to-use formulas may not, so always check the label for a surfactant statement.
Coverage Area and Concentration Ratio
Ready-to-use products like Ortho WeedClear and Bonide Deadweed Brew offer convenience but a fixed coverage limit (typically 20,000 sq ft per gallon). Concentrates like Southern Ag Atrazine and Control Solutions Eraser let you adjust the mix strength based on weed maturity: a higher concentration for mature dollar weed clumps, a lighter mix for young seedlings. A 1-gallon concentrate bottle can yield 8 to 32 gallons of mixed spray depending on the product, translating to 4,000 to 16,000 sq ft of coverage per bottle. Always measure your lawn or target area before buying to ensure you choose the right format — buying a gallon of ready-to-use for a 500 sq ft border is wasteful, while buying a quart concentrate for a single spot treatment forces you to store unused mixed chemical.
FAQ
Does atrazine kill dollar weed in St. Augustine grass?
Can I use Roundup Weed and Grass Killer III on my lawn?
How long does it take for dollar weed to die after spraying?
Final Thoughts: The Verdict
For most gardeners, the best weed killer for dollar weed winner is the Southern Ag Atrazine because it combines selective lawn safety with proven efficacy against dollar weed’s root network and provides residual pre-emergent protection for the entire season. If you want a handy spot-treatment tool for cool-season turf without mixing chemicals, grab the Ortho WeedClear with Comfort Wand. And for organic gardeners or total-kill jobs in non-lawn areas, nothing beats the application range of the Bonide Captain Jack’s Deadweed Brew.