Answering the question, these herbicides are among the most practical for St. Augustine grass: selective herbicides that target broadleaf weeds, non-selective glyphosate options for spot treatment, and lawn-feed blends that combine weed control with fertilization. The top picks below are best for homeowners seeking reliable weed suppression without harming St. Augustine lawns. Each product is best for specific weed types, application needs, and maintenance goals. A quick buyer’s table is included to compare core details at a glance.
| Product | Best For | Type | Notes |
|---|---|---|---|
| Southern Ag 006130 Atrazine | St. Augustine and centipede weed control | Selective herbicide | Quarts cover large areas; targeted weed control |
| Southern Ag Atrazine St. Augustine Weed Killer | Broadleaf weed suppression in St. Augustine | Selective herbicide | Keeps centipede lawn in mind |
| Buccaneer 5 Extra Glyphosate (2.5 Gal) | Non-selective spot treatment | Non-selective herbicide | Great for tough, persistent weeds |
| Compare-N-Save Glyphosate Concentrate | General weed clearing, large areas | Non-selective herbicide | Rainproof in 2 hours; visible results fast |
| LESCO 50 lb Weed & Feed with Penoxsulam | Weed control plus fertilizer for St. Augustine | Weed & feed | Slow-release feeding; Floratam-safe |
Southern Ag 006130 Atrazine St. Augustine Weed Killer
Active use targets common weeds in St. Augustine and centipede grasses. Best for homeowners who want to treat broad areas efficiently with a quart-sized container. The product is designed for use on lawns that include St. Augustine varieties, and it helps control a range of annual broadleaf weeds. Best for: large yards where selective weed control in St. Augustine is needed. Caution: follow label directions closely to prevent over-application and potential lawn stress.
Southern Ag Atrazine St. Augustine Grass Weed Killer
This product emphasizes suppression of a wide range of broadleaf weeds while remaining compatible with St. Augustine grasses and centipede lawns. It is suitable for users seeking broadleaf weed control with an emphasis on St. Augustine turf resilience. Best for: yard owners who want a straightforward, broad-spectrum weed control option for established St. Augustine lawns. Caution: apply as directed to avoid turf injury in hot or stressed conditions.
Buccaneer 5 Extra Glyphosate Concentrate
Glyphosate-based, non-selective weed killer suited for spot treatment and cleanup on mixed lawns. Best for: homeowners needing strong, fast-acting weed removal in small patches or edging around walkways. Caution: not selective; avoid spraying on desirable St. Augustine grass if you want to preserve grass health around treated areas.
Compare-N-Save Glyphosate Concentrate
A 2.5-gallon concentrate designed to deliver fast results with visible weed reduction within days. Best for: large properties needing a cost-effective, non-selective weed killer. Caution: as a non-selective herbicide, it will kill or severely damage any green plant it contacts, including desirable grass if not carefully applied.
LESCO 50 lb Weed & Feed With Penoxsulam
This product blends weed control with a fertilizer program designed for St. Augustine grass. Best for: lawn owners who want ongoing weed suppression tied to nutrient delivery, promoting thicker turf and healthier color. Caution: ensure proper application timing and avoid over-watering immediately after application to maximize results.
Buying Guide: Important Considerations For St. Augustine Grass Weeds
St. Augustine lawns respond to careful weed management. Here are practical questions and considerations to guide your choices:
- What weed types are you targeting? Broadleaf weeds respond best to selective herbicides like atrazine formulations, while non-selective glyphosate products handle tough patches but require precision to protect grass.
- Is the product compatible with your grass type? Floratam-tolerant options and compatibility notes reduce risk of turf damage.
- Do you prefer a weed-only treatment or a weed-and-feed approach? If you want to feed the lawn at the same time, weed-and-feed products may offer convenience but require careful nutrient planning.
- What area size do you treat? Concentrates and larger containers are better for big yards; smaller containers may be more cost-effective for limited patches.
- What season is best for application? Warm-season grasses often respond to late spring through summer applications; follow label timing for best results.
- Are there safety and application precautions? Always follow label directions, protect desirable plants, and consider weather conditions to avoid drift and runoff.
Frequently Asked Questions
- Can I use glyphosate on St. Augustine grass? Yes, but use it for spot treatment and avoid spraying on healthy grass. Non-selective glyphosate will kill anything it touches.
- Is atrazine safe for St. Augustine? When used as directed, atrazine products can control many broadleaf weeds in St. Augustine and centipede lawns, but follow label restrictions and local guidelines.
- What is the advantage of a weed-and-feed product? It combines weed control with essential nutrients, supporting growth while reducing weed pressure. Ensure the nutrient mix fits your lawn’s needs.
- How often should I treat weeds in St. Augustine grass? Frequency depends on weed pressure and product type. Follow label timing and avoid over-application which can stress the lawn.
- Can I use these products on all St. Augustine varieties? Several products note compatibility with common St. Augustine varieties; verify with the product label for your specific cultivar.
- What safety steps should I take during application? Wear protective clothing, avoid wind drift, and water the lawn as recommended after application to help product absorption and minimize residue on non-target areas.