How to Kill Dollarweed (Pennywort) in Zoysiagrass Without Hurting Your Lawn
Direct Agronomic Answer
To selectively kill Dollarweed (Pennywort) in Zoysiagrass without damaging your turf, apply Drive XLR8 (Quinclorac 18.92%), SpeedZone Lawn Weed Killer (2,4-D 28.57%, Mecoprop-p 5.88%, Dicamba 1.71%, Carfentrazone-ethyl 0.62%) when air temperatures are between 60°F and 85°F.
For Bermudagrass and cool-season turf, 2,4-D or SpeedZone is effective. Reducing irrigation frequency is vital as Dollarweed indicates waterlogged conditions.
1. Labeled Safe Herbicides That Kill Dollarweed (Pennywort) in Zoysiagrass
| Recommended Product | Active Ingredient & Group | Application Temp (°F) | Surfactant & Mixing Protocol | Where to Buy |
|---|---|---|---|---|
| Drive XLR8 EPA Reg. 7969-272 |
Quinclorac 18.92% Group 4 (Synthetic Auxin / Quinoline Carboxylic Acid) |
60°F – 85°F Rainfast: 1h |
Requires Methylated Seed Oil (MSO) surfactant at 1.5 tbsp (0.75 fl oz) per gallon of water for effective cuticle penetration on multi-tiller crabgrass. | Check Price at DoMyOwn View on Amazon |
| SpeedZone Lawn Weed Killer EPA Reg. 2217-833 |
2,4-D 28.57%, Mecoprop-p 5.88%, Dicamba 1.71%, Carfentrazone-ethyl 0.62% Group 4 + Group 14 (Synthetic Auxins + PPO Inhibitor) |
50°F – 85°F Rainfast: 3h |
Do NOT add surfactant. Adding NIS or MSO increases ester volatility and causes severe contact burn on desirable cool-season turf. | Check Price at DoMyOwn View on Amazon |
| Celsius WG EPA Reg. 432-1507 |
Thiencarbazone-methyl 8.7%, Iodosulfuron-methyl-sodium 1.9%, Dicamba 57.4% Group 2 + Group 4 (ALS Inhibitors + Benzoic Acid Auxin) |
65°F – 95°F Rainfast: 4h |
Apply with Non-Ionic Surfactant (NIS) at 1 tsp per gallon of water. Specifically engineered not to stunt warm-season turf during summer heat up to 95°F. | Check Price at DoMyOwn View on Amazon |
| Image Kills Nutsedge EPA Reg. 228-719 |
Imazaquin 3.3% Group 2 (ALS Inhibitor / Imidazolinone) |
65°F – 90°F Rainfast: 6h |
Ready-to-mix liquid formulation contains surfactant; additional NIS is not required for standard broadcast or spot treatments. | Check Price at DoMyOwn View on Amazon |
| Hi-Yield Atrazine Weed Killer EPA Reg. 34911-15-7401 |
Atrazine 40.8% Group 5 (Photosystem II Inhibitor / Triazine) |
50°F – 85°F Rainfast: 6h |
Do NOT add surfactant when spraying actively growing St. Augustine or Centipede above 80°F to avoid foliar yellowing. Irrigate lightly within 48 hours for root uptake. | Check Price at DoMyOwn View on Amazon |
3. Optimal Seasonal Timing & Temperature Thresholds
Spray in spring or fall when Dollarweed is actively sending up new circular leaves.
Sequential applications 2 to 3 weeks apart are required to eradicate deep underground rhizomes.
4. Diagnostic Checklist: Confirm It Is Dollarweed (Pennywort) Before Spraying
- Bright green, circular silver-dollar-shaped leaves with scalloped margins
- Petiole attaches directly in the center of the leaf undersurface (peltate umbrella-like)
- Spreading fleshy rhizomes and tubers thriving in over-irrigated waterlogged soil
Not 100% sure? Use our AI Photo Weed Scanner or review the full Dollarweed (Pennywort) Botanical Profile.