Crabgrass control in St. Augustine lawns requires selecting products that target broadleaf and grassy weeds without harming the turf. This guide highlights five effective options commonly used in St. Augustine and provides practical guidance on when and how to apply them. Each product is evaluated for best-use scenarios, possible limitations, and who should consider choosing it. The buyer will find concise comparisons to help decide which product fits their lawn’s needs.
| Product | Best For | Active Weed Targets | Notes |
|---|---|---|---|
| Southern Ag 006130 Atrazine St. Augustine Weed Killer | St. Augustine and Centipede lawns seeking broadleaf weed control | Broadleaf weeds; some grasses | Quart size covers ~3,720 sq ft |
| Southern Ag Atrazine St. Augustine Grass Weed Killer | St. Augustine and centipede lawns needing suppression of crabgrass | Broadleaf weeds; suppression of crabgrass | Good option for larger areas |
| BioAdvanced All-in-One Weed & Crabgrass Killer, Ready-To-Spray | Lawn owners wanting broad weed control plus crabgrass management | 200+ broadleaf weeds; crabgrass | Ready-to-spray convenience |
| Agralawn Crabgrass Killer | St. Augustine and some common warm-season grasses | Crabgrass and select grasses; leaf absorption | Post-emergent and leaf-uptake formula |
| BioAdvanced All-In-One Lawn Weed & Crabgrass Killer (Concentrate) | Lawn owners seeking deep root control for tough weeds | Crabgrass and many broadleaf weeds | Concentrate; longer-term control potential |
Southern Ag 006130 Atrazine St. Augustine Weed Killer (32 oz)
Best for mid-size St. Augustine lawns looking for reliable broadleaf weed control. This quart-sized bottle treats up to 3,720 square feet and is designed to work in St. Augustine and centipede grasses. Use when weeds are actively growing and the lawn is not under heat stress. Best for homeowners who want a straightforward, ready-to-apply solution that targets common lawn weeds without heavy reliance on multiple products. Caution: Atrazine can affect some ornamentals and may require careful application to avoid drift onto non-target plants.
Southern Ag Atrazine St. Augustine Grass Weed Killer (1 Gallon)
Better for larger lawns needing sustained suppression of crabgrass alongside broadleaf weed control. This one-gallon option targets a broad spectrum of weeds and is suitable for St. Augustine and centipede grasses. Choose this if you have a larger yard or want fewer fill-ins over time. Consider that it focuses on suppression and broadleaf control; aggressive crabgrass management may require follow-up treatments or additional products depending on infestation levels.
BioAdvanced All-in-One Weed & Crabgrass Killer, Ready-To-Spray
Best for owners seeking a combined solution that controls over 200 broadleaf weeds and crabgrass with convenient, ready-to-spray application. It’s labeled as safe for lawns when used as directed, and it offers quick rain resistance once dry. This option is well-suited for homeowners who want an all-in-one product without measuring concentrates. Limitation: sprayer consistency and even coverage can affect results in dense thatch or uneven lawns.
BASF Drive XLR8 Crabgrass Killer for Lawn & Turf
Best for homeowners needing fast action and longer residual control. Drive XLR8 provides up to 30 days of residual weed suppression and is effective against a wide range of grasses and broadleaf weeds, with a quick spray-to-uptake profile. It’s rainfast quickly, making it a solid option for lawns with variable weather patterns. Limitation: some lawns may require follow-up applications for persistent weed pressure, and it is a larger-volume concentrate.
BioAdvanced All-In-One Lawn Weed & Crabgrass Killer (Concentrate)
Best for precision control when you prefer to mix a concentrate for targeted weed-and-feed needs. It claims to kill crabgrass and many broadleaf weeds without harming common lawn grasses like Kentucky bluegrass, ryegrass, or fescue when used as directed. This option is suitable for homeowners who want tailored rates and extended effectiveness. Caution: performance depends on proper dilution and uniform application on uneven turf.
Buying Guide: Key Considerations for Crabgrass Control in St. Augustine Lawns
- Target compatibility: Ensure the product is labeled for St. Augustine or centipede grasses to avoid turf injury.
- Weed spectrum: If you face both crabgrass and broadleaf weeds, consider all-in-one formulas or products with broadleaf efficacy plus crabgrass control.
- Mode of application: Ready-to-spray products offer convenience, while concentrates require mixing but can be cost-effective for larger areas.
- Residual effect: Some products offer longer weed suppression, reducing the need for frequent applications. Consider your mowing schedule and local climate when selecting.
- Weather and timing: Apply during active weed growth and avoid extreme heat or drought; follow label directions for soil moisture and irrigation after application.
- Turf safety: Look for products that advertise low risk to St. Augustine and centipede grasses to minimize yellowing or turf damage.
- Application limits: Be mindful of nearby ornamentals and landscaping beds to prevent drift or unintended exposure.
FAQ
- Q: Which product is best for a medium-sized St. Augustine lawn with crabgrass? A: A product labeled for St. Augustine with crabgrass suppression, such as the Southern Ag Atrazine St. Augustine Weed Killer in a larger size, is a practical choice for medium-sized lawns.
- Q: Can I use these products if it rained recently? A: Some products are rainfast within about an hour after drying, but always follow the label’s weather guidelines and avoid applying before heavy rainfall unless specified.
- Q: Do these herbicides harm other lawn grasses? A: Most products are designed to be safe for common turfgrasses when used as directed; however, always verify compatibility with your specific grass species and avoid drift onto ornamentals.
- Q: Should I mix multiple products for better control? A: It’s generally better to select a single product compatible with your turf and weed profile. Mixing products can lead to unpredictable results and potential turf injury.
- Q: How long before I see results? A: Many products act on contact or within a few days; some cause visible weed browning within 3–7 days, with full effect over several weeks depending on weed pressure.
- Q: Is a lawn weed and crabgrass killer the same as a fertilizer? A: No. Weed killers target unwanted plants, while fertilizers promote turf growth. Some products combine both functions, but read the label to confirm.