Best Herbicides for St Augustine Grass: Effective Weed Control Options
St Augustine grass requires targeted weed control to maintain thick, healthy turf. The following picks focus on products designed to suppress or kill common lawn weeds in St Augustine lawns, including crabgrass, broadleaf weeds, and unwanted grasses. Each option provides specifics on coverage, application, and suitability for St Augustine and centipede grasses. The list prioritizes products available on Amazon for convenient checkout and reliable branding, with notes on how they work in typical residential settings.
| Product | Brand | Notes |
|---|---|---|
| Southern Ag 006130 Atrazine St. Augustine Weed Killer 32oz | Southern Ag | For St Augustine and centipede grasses; treats up to 3,720 sq ft per quart. |
| Southern Ag Atrazine St. Augustine Grass Weed Killer 1 Gallon | Southern Ag | Kills many broadleaf weeds; suppresses crabgrass; also usable in centipede lawns. |
| Southern Ag Atrazine St. Augustine Grass Weed Killer (1 Gallon) + Surfactant | Southern Ag | Enhanced coverage and penetration; includes surfactant; suppresses crabgrass. |
| Compare-N-Save Glyphosate Concentrate Grass & Weed Killer | Compare-N-Save | Glyphosate-based; rainproof in 2 hours; makes up to 10 gallons of spray. |
| Gordon’s Ornamec 170 Grass Herbicide | GORDON’S | Fluazifop-P-butyl; labeled for use around ornamental plants and landscape areas. |
Note: The products listed above are intended for use on St Augustine grass and related lawns. Always read the label for specific usage instructions, safety precautions, and compatibility with your lawn species and nearby ornamentals.
Southern Ag Atrazine St. Augustine Weed Killer 32oz
- One quart treats 3,720 sq ft, offering coverage for medium to large lawns.
- Controls broadleaf weeds in St. Augustine and centipede grasses, helping to reduce competition.
- Package weight and handling details support storage and application planning.
Southern Ag Atrazine St. Augustine Grass Weed Killer 1 Gallon
- Kills many broadleaf weeds while also usable in centipede lawns.
- Provides suppression of crabgrass, supporting early-season weed control.
- Designed for larger application areas with a gallon size for convenience.
Southern Ag Atrazine St. Augustine Grass Weed Killer (Surfactant Included)
- The Atrazine weed killer targets weeds common to St. Augustine and centipede lawns.
- Surfactant boosts coverage and penetration for more effective weed control.
- Also provides suppression of crabgrass as part of a broader lawn care plan.
Compare-N-Save Glyphosate Concentrate Grass & Weed Killer
- Contains 41% glyphosate for broad-spectrum weed control.
- Rainproof in approximately 2 hours, enabling flexible scheduling after rain events.
- Makes up to 10 gallons of ready-to-use spray for multiple applications.
Gordon’s Ornamec 170 Grass Herbicide
- Contains Fluazifop-P-butyl at 1.70% for selective grass control in ornamental settings.
- Suitable for use around ornamental plants, groundcovers, shrubs, and landscape beds.
- Can be mixed at a rate that supports targeted, moderate-area treatment.
Buying Guide: Key Purchase Considerations For St Augustine Weed Control
When selecting a herbicide for St Augustine grass, it helps to weigh weed type, lawn health, and nearby ornamentals. Atrazine-based products often provide broad weed suppression in warm-season grasses, but may have rotational restrictions or usage guidelines in certain areas. Glyphosate offers broad-spectrum control but is non-selective, requiring careful targeted application to avoid damage to desired grass. Ornamec (fluazifop-P-butyl) emphasizes selectivity toward grassy weeds, making it suitable for lawns with ornamental plantings, but this broader approach may limit effectiveness on broadleaf weeds.
Application considerations include: coverage per acre or square footage, required water volumes, surfactants or stickers, and the inclusion of additives or surfactants to improve spread. The presence of a surfactant, as seen in one Southern Ag option, can enhance penetration and weed kill, particularly in dry or glossy leaf conditions. Always follow label directions for timing, temperature, and irrigation after application to maximize results and minimize turf stress.
Comparative perspectives include:
- Broad-spectrum versus selective control: Glyphosate provides broad control but lacks selectivity, while Atrazine-based products target grasses and some broadleaf weeds but may be restricted in certain regions due to environmental concerns.
- Surfactant inclusion: Surfactants improve coverage and wetting on leaf surfaces, potentially enhancing effectiveness but adding an extra component to manage.
- Ornamental considerations: Some products, like Ornamec, emphasize safety around ornamentals, which is crucial for landscape beds adjacent to lawns.
For best results, match the product to the weed profile of your lawn, apply during appropriate weather conditions, and monitor for post-application recovery or regrowth. Consider integrating pre-emergent strategies and proper lawn care practices (mowing height, watering regime, and nutrient management) to sustain weed suppression and turf vigor over time.