Finding a weed killer that works well with St. Augustine grass can be challenging. The products below are selected for their compatibility with St. Augustine varieties and Centipede grass, durability, and broad weed control. This guide compares top-rated options from reputable brands to help you maintain a lush, weed-free lawn.
Product Comparison at a Glance
| Product | Brand | Key Use | Note |
|---|---|---|---|
| Southern Ag 006130 Atrazine St. Augustine Weed Killer 32oz | Southern Ag | St. Augustine and Centipede weed control | Treats up to 3,720 sq ft per quart |
| Southern Ag Atrazine St. Augustine Grass Weed Killer, 1 Gallon | Southern Ag | Kills broadleaf weeds; suppression of crabgrass | Includes centipede grass applications |
| Hi-Yield Atrazine Weed Killer | VPG | St. Augustine & Centipede grass weed control | Atrazine 4.00% with multiple targeted weeds |
| BioAdvanced 3-in-1 Weed and Feed for Southern Lawns | BioAdvanced | Weed control plus lawn feeding for Southern lawns | Up to 6 months weed protection |
| BioAdvanced Season Long Lawn Weed Killer + Preventer (10 lb) | BioAdvanced | Weed killing and preventive treatment for Southern lawns | Treats up to 4,000 sq ft |
Note: Always follow label instructions for your specific grass variety and local regulations. The list below highlights five products most relevant to St. Augustine grass weed management.
Southern Ag 006130 Atrazine St. Augustine Weed Killer 32oz
Designed specifically for St. Augustine lawns, this atrazine-based weed killer targets common broadleaf and grassy invaders affecting Centipede and St. Augustine lawns. A quart covers up to 3,720 sq ft, making it a cost-effective choice for medium-to-large lawns. The product’s focus on St. Augustine compatibility helps minimize risk to desired turf while delivering weed suppression where needed. Application guidance on the label should include precautions for non-target plants and re-entry times after treatment.
Southern Ag Atrazine St. Augustine Grass Weed Killer, 1 Gallon
This gallon-sized Atrazine formula is a versatile option for extended weed control in St. Augustine and Centipede lawns. It provides broadleaf weed suppression and active use in centipede grass, with additional suppression of crabgrass in some conditions. The larger volume reduces the need for frequent reapplication, but as with all atrazine products, follow label directions for best results and environmental safety. Beneficial where longer treatment intervals are preferred.
Hi-Yield Atrazine Weed Killer
Hi-Yield Atrazine Weed Killer offers a targeted atrazine formulation suitable for St. Augustine and Centipede grasses. With a 4.00% atrazine content, this product targets annual bluegrass, chickweed, and other common lawn weeds. It is intended for use on St. Augustine and Centipede grass, making it a strong fit for Southern lawns prone to broadleaf and grassy invaders. As with all atrazine-based products, follow the label for safe mixing, application timing, and environmental considerations.
BioAdvanced 3-in-1 Weed and Feed for Southern Lawns
This 3-in-1 product combines weed control with lawn feeding for Southern lawns, including St. Augustinegrass ( Floratam varieties included). It provides up to six months of weed prevention alongside nourishment for your turf, helping reduce a common weed re-emergence cycle. The formulation is designed to be compatible with Southern turf types, delivering a balanced approach to weed management and lawn care. Beneficial for homeowners seeking a simplified, all-in-one solution.
BioAdvanced Season Long Lawn Weed Killer + Preventer
This granulated product targets a broad spectrum of listed broadleaf and some grassy weeds while also providing season-long preventive protection for Southern lawns. It is designed to treat up to 4,000 square feet and is suitable for St. Augustinegrass varieties. The long-lasting layer of protection aims to reduce new weed establishment across the growing season, offering a proactive approach to lawn care. As with all granular weed killers, uniform application and watering are important for optimal results.
Buying Guide
When choosing a weed killer for St. Augustine grass, consider the following factors to ensure better results and turf health:
- Grass compatibility: Confirm the product lists St. Augustinegrass or Floratam varieties on the label to minimize turf damage.
- Target weed spectrum: Determine whether you need broadleaf weed control, grassy weed control, or a combination, and select accordingly.
- Application method: Choose ready-to-use liquids, concentrates (requiring mixing), or granular formulas based on ease and garden size.
- Soil and environmental safety: Atrazine-based products can have environmental restrictions; review local guidelines and buffer zones near water sources.
- Seasonality and duration: Some products offer immediate knockdown, while others provide weeks to months of preventive protection. Align with your lawn’s growth cycle.
- Lawn health considerations: Some products double as lawn fertilizers or claim prevention benefits, which can reduce the need for separate feedings.
- Re-entry and watering instructions: Adhere to waiting periods before children or pets can re-enter treated areas, and follow watering guidelines to activate the product.
- Safety and handling: Wear protective gear as recommended and store products out of reach of children and pets.
For best results, rotate between products with different active ingredients across seasons to mitigate weed resistance. Always follow the product label for exact application rates, compatible grass types, and any regional restrictions. Consider integrating a regular lawn maintenance routine—mowing height, irrigation, and staggered weed-control treatments—to maintain a healthy, weed-resistant St. Augustine lawn.