Answering the common question for St. Augustine lawn care: these herbicides are designed to control broadleaf and grassy weeds without drastically harming St. Augustine grass when used as directed. This guide highlights five products that are well-suited for St. Augustine lawns, explains who they’re best for, and notes practical considerations. Perfect for homeowners, landscapers, and property managers seeking reliable weed control with minimal turf risk.
| Product | Best For | Notes |
|---|---|---|
| Southern Ag 006130 Atrazine St. Augustine Weed Killer | Light to moderate weed pressure on established St. Augustine | Effective for broadleaf weeds; covers large areas per quart |
| Southern Ag Atrazine St. Augustine Grass Weed Killer (1 Gallon) | Broadweed control and crabgrass suppression | Versatile option for larger lawns |
| Atticus Azion XP MSM Turf Herbicide (8-oz) | Selective postemergence weed control in Bermudagrass and St. Augustine | High concentration metsulfuron-methyl formulation |
| St Augustine Grass Fertilizer – Liquid Lawn Food (1 Gallon) | Fertilization combined with color and growth boost | Not a weed killer; supports overall turf health |
| Ortho WeedClear Weed Killer for Lawns with Comfort Wand (1 gal) | Easy-to-use, lawn-friendly broadleaf weed control | Ready-to-use spray with wand for precise application |
Southern Ag 006130 Atrazine St. Augustine Weed Killer
Product highlights: Treats 3,720 sq ft per quart; controls weeds in St. Augustine and centipede grasses. Best for homeowners with medium weed pressure on established lawns. Suitable for lawns where broadleaf weeds are the primary issue. Caution: Atrazine can affect ornamentals or nearby sensitive plants if misapplied; follow label directions precisely to minimize risk to non-target vegetation. This option is best for users needing broad coverage per application and for those already operating within labeled turfgrass species.
Southern Ag Atrazine St. Augustine Grass Weed Killer (1 Gallon)
Product highlights: Kills many broadleaf weeds and is also used in centipede grass; provides suppression of crabgrass. Best for larger lawns that require ongoing weed suppression across a season. Choose this if you need a versatile, one-gallon option for extended coverage. Limitation: As with Atrazine-based products, follow label timing and application rates to minimize effects on non-target grasses and prevent runoff.
Southern Ag Atrazine St. Augustine Grass Weed Killer, 1 Gallon & Surfactant
Product highlights: Combines Atrazine weed killer with a non-ionic surfactant to improve spreading and leaf coverage. Best for users who want a ready-to-use combination to enhance weed control in St. Augustine and centipede grass. Selecting this option improves efficacy on waxy or hard-to-wet leaves. Limitation: Surfactants can increase weed kill on non-target plants if misapplied; always follow label guidelines for turf and ornamentals in proximity.
Atticus Azion XP MSM Turf Herbicide (8-oz)
Product highlights: Contains 60% metsulfuron-methyl; designed for selective post-emergence weed control in Bermudagrass and St. Augustine grass. Best for areas with emerged weeds like ryegrass, foxtail, Virginia buttonweed. Choose this if you need a targeted herbicide for stubborn broadleaf and grassy weeds. Caution: Do not apply to other turfgrass species as plant injury may occur; consult the label for tolerant turfgrass details and timing for best results.
Agralawn Crabgrass Killer (2 lb)
Product highlights: Targets St. Augustine, Bermuda, Bahia and Centipede grasses; designed to wipe out weeds with leaf absorption. Best for lawns facing crabgrass pressure in mixed grass areas. Notably safe for St. Augustine when used as directed. Limitation: Not a selective herbicide for all weed types; ensure it is suitable for your turf species before application to avoid turf damage.
Ortho WeedClear Weed Killer for Lawns with Comfort Wand
Product highlights: Ready-to-use formula with Comfort Wand for easy, precise application; kills dandelion and clover among common lawn weeds without harming grass when used as directed. Best for homeowners who want a fast, user-friendly solution with minimal setup. Limitation: As a ready-to-use product, it may require more frequent reapplication for persistent infestations and is generally best for spot treatment rather than bulk coverage.
Buying Guide
What should you consider when choosing a St. Augustine herbicide?
- Turf compatibility: Ensure the product is labeled for St. Augustine and any adjacent grasses to avoid injury.
- Weed type and scope: Identify whether you need broadleaf weed control, grassy weed suppression, or post-emergence action for emerged weeds.
- Application method: Consider whether you prefer a concentrate with mixing (e.g., Atrazine-based products) or a ready-to-use spray (e.g., Ortho WeedClear).
- Coverage area: Larger lawns may benefit from gallon-size formulations; smaller lawns can use quart or ready-to-use options.
- Non-target safety: Be mindful of nearby ornamentals, driveway edges, and irrigation paths to minimize drift or runoff.
FAQ
- What herbicide is best for St. Augustine with crabgrass?
– Atrazine-based products are commonly used for broad weed suppression; combine with proper mowing and watering schedules for best results. - Can I use post-emergence metsulfuron-methyl products on St. Augustine?
– Yes, in labeled formulations like Azion XP, designed for selective post-emergence control in St. Augustine; always follow label directions. - Is a surfactant necessary for killing weeds in St. Augustine?
– Surfactants improve leaf coverage for many products; use only when the label recommends or requires it. - Are ready-to-use weed killers safe for St. Augustine lawns?
– Generally, yes when used as directed; they offer convenience but may require more frequent applications for persistent weeds. - Should I apply herbicides during heat waves or drought?
– It’s best to apply under moderate temperatures and adequate soil moisture, following label timing to minimize stress on the turf. - Can these products affect nearby ornamentals?
– Yes; always treat according to the label and avoid drift toward non-target plants.