St. Augustine grass requires targeted weed control that protects its delicate root system while keeping lawns lush. The products below are popular choices for homeowners seeking to manage broadleaf weeds and crabgrass in St. Augustine turf. This guide highlights five reliable options, compares their primary features, and offers practical buying tips to help you choose the right product for your yard.
| Product | Brand | Key Benefit | Recommended For |
|---|---|---|---|
| Southern Ag Atrazine St. Augustine Grass Weed Killer, 1 Gallon | Southern Ag | Kills broadleaf weeds; suppresses crabgrass | St. Augustine and centipede grasses |
| Southern Ag 006130 Atrazine St. Augustine Weed Killer 32oz | Southern Ag | Treats large areas; targets St. Augustine and centipede weeds | Lawn wide-area areas |
| Scotts Turf Builder Southern Triple Action | Scotts | 3-in-1 formula: weed killer, insect preventer, fertilizer | St. Augustine, centipede, and other southern grasses |
| Hi-Yield Atrazine Weed Killer RTS | VPG | Atrazine-based control for several common weeds | St. Augustine and centipede grasses |
| BioAdvanced 3-in-1 Weed and Feed for Southern Lawns | BioAdvanced | Weed prevention plus feeding for southern lawns | St. Augustinegrass including Floratam |
The following sections detail five select products with practical notes on application, coverage, and weed targets. Each entry includes a clickable product link, an image, and a concise feature summary to help you compare options quickly.
Southern Ag Atrazine St. Augustine Weed Killer
This atrazine-based formula is designed for St. Augustine grass and centipede lawns, offering broadleaf weed control with the added benefit of crabgrass suppression. It’s suitable for larger turf areas and provides a straightforward application path for homeowners dealing with common warm-season weeds. The product’s versatility makes it a practical choice for seasonal weed cycles and preventative care in southern lawns.
Southern Ag Atrazine St. Augustine Weed Killer 32oz
This 32-ounce bottle is a compact option for treating moderate lawn areas. It targets weeds common in St. Augustine turf and supports weed control in centipede grasses as well. The sizing is convenient for homeowners managing smaller to mid-sized lawns or for spot treatments where weed pressure is concentrated.
Scotts Turf Builder Southern Triple Action
Scotts Turf Builder Southern Triple Action combines weed control, fire ant prevention, and lawn feeding in a single application. It’s designed for southern grasses, including St. Augustine and Floratam, and provides protection against several pests for up to six months. This all-in-one approach can simplify lawn care by addressing weed pressures and providing nutrients to strengthen heat- and drought-stressed lawns.
Hi-Yield Atrazine Weed Killer RTS
Hi-Yield Atrazine Weed Killer RTS focuses on Atrazine-based weed control for St. Augustine and centipede grasses. It targets common lawn weeds and is suitable for treating lawn areas where broadleaf weeds are prevalent. The RTS formulation is designed for ready-to-use convenience, making it a practical option for homeowners seeking straightforward application without mixing.
BioAdvanced 3-in-1 Weed and Feed for Southern Lawns
This BioAdvanced product provides a 3-in-1 approach tailored for southern lawns, including St. Augustinegrass. It combines weed control with lawn fertilization, delivering up to six months of protection against listed broadleaf and grassy weeds, while nourishing the lawn to maintain a healthy, resilient turf. It’s a suitable option for homeowners who want ongoing weed prevention alongside feeding.
BioAdvanced Season Long Lawn Weed Killer + Preventer
This product protects southern lawns for up to six months, targeting a range of listed broadleaf weeds and preventing crabgrass and other invading grasses. It’s designed to treat up to 4,000 square feet and is suitable for St. Augustine turf, helping maintain a weed-free, well-nourished lawn throughout the growing season.
Sunniland St.Augustine Weed & Feed
Designed for St. Augustine turf, Sunniland Weed & Feed is a granulated option that combines weed control with fertilization. The product is formulated for ease of spreading and is suitable for two applications in spring and fall. This approach supports ongoing weed management while promoting lawn vigor in various St. Augustine varieties.
Hi-Yield Atrazine Weed Killer RTS (32 oz)
Hi-Yield RTS Atrazine is a ready-to-use option that targets henbit, clover, chickweed, and other common lawn weeds. It’s intended for use on St. Augustine and centipede grasses, and the 32-ounce bottle can treat approximately 3,720 square feet. This product is suitable for homeowners seeking a convenient, pre-mixed solution for regular weed-control cycles.
Buying Guide: Key Factors To Consider
When selecting a weed killer for St. Augustine grass, consider weed types, safety for warm-season lawns, application method, coverage area, and lawn health benefits beyond weed control. Atrazine-based products are effective for general broadleaf and some grassy weeds but require careful application to minimize impact on desirable turf and nearby ornamentals. Some products combine weed control with fertilizer or pest prevention, which can simplify lawn care but may not fit every lawn’s needs.
Coverage area and bottle size matter: larger yards benefit from gallon or multi-quart formulations, while smaller lawns may suffice with quart-sized products. RTS (ready-to-use) formulations are convenient for spot treatments, whereas concentrate formulas may require mixing but can be more cost-effective per square foot. Always follow product labels for St. Augustine compatibility, application timing, irrigation requirements, and re-entry intervals to protect pets and people.
Safety and environmental considerations are essential. Atrazine products should be used according to label directions to prevent runoff and minimize impacts on non-target plants. If your lawn includes Floratam variants or neighboring warm-season grasses, verify compatibility and retreatment intervals. Consider whether you prefer a stand-alone weed killer or a combined weed killer with fertilizer or pest prevention, and balance short-term weed control with long-term lawn health and resilience.
For best results, diagnose the predominant weed species in your lawn before choosing a product. Some products excel at broadleaf weed control, while others offer superior crabgrass suppression or prolonged prevention. Early-season applications, proper watering after treatment, and adherence to recommended application rates all contribute to effective weed management without compromising St. Augustine grass health.
By selecting a product tailored for St. Augustine and centipede grasses, you reduce the risk of turf damage and maximize weed control. The options above span ready-to-use and concentrated formulas, single-purpose and multi-benefit formulations, giving homeowners flexible choices across different lawn sizes and weed pressures.