How To Remove St. Augustine Grass: A Comprehensive Eradication Strategy

St. Augustine grass is a vigorous, stoloniferous perennial that requires a multi-stage approach combining mechanical excavation, herbicide application, and soil sterilization to prevent regrowth. Successful eradication demands a commitment to removing all underground runner systems, as even a small segment of rhizome can regenerate a new colony within a single growing season.

Pre-Operation Site Assessment and Equipment Requirements

Removing St. Augustine (Stenotaphrum secundatum) is physically demanding due to its thick, coarse texture and aggressive rooting habit. Before breaking ground, evaluate the scale of the infestation. Small patches can be managed with manual removal, while extensive infestations require a systemic chemical-to-mechanical workflow.

• Essential Gear and Tools:
  
  
  • Mechanical Sod Cutter (Self-propelled, 12-to-18-inch cutting width).
  • Heavy-duty landscape rake and garden fork.
  • Glyphosate-based herbicide (minimum 41% active ingredient).
  • Non-ionic surfactant for improved leaf penetration.
  • Personal Protective Equipment (PPE): Chemical-resistant gloves, eye protection, and long-sleeved clothing.
  • Soil rototiller or power cultivator.
• Mandatory Prerequisite Knowledge:
  
  
  • Growth Habit: St. Augustine spreads via stolons (above-ground stems). Identify if the infestation has reached neighboring beds through subterranean runners.
  • Moisture Levels: Soil should be slightly moist but not saturated to facilitate clean root extraction.
  • Environmental Conditions: Do not apply herbicides if rain is forecasted within 24 hours or if wind speeds exceed 5 mph to prevent drift.
• Benchmarks:
  
  
  • Budget: $150–$300 for rental equipment and high-grade chemicals.
  • Timeframe: 14 to 21 days for full chemical kill-off, followed by 1–2 days for mechanical removal and soil prep.

Technical Execution Workflow for Total Grass Removal

Step 1: Systemic Herbicide Application

The most effective way to eliminate St. Augustine is to kill the root system before excavation. Apply a high-quality, systemic, non-selective herbicide directly to actively growing green foliage. Ensure the grass is healthy and not under drought stress, as the plant must be actively translocating nutrients for the poison to reach the root nodes.

1. Mix the glyphosate solution according to the manufacturer’s instructions, typically 2 to 3 ounces per gallon of water.
2. Add a non-ionic surfactant to break the waxy cuticle layer of the St. Augustine blades, which otherwise repels liquids.
3. Spray the entire area thoroughly.
4. Allow the herbicide 10 to 14 days to circulate through the stolon network. You will observe yellowing and eventual browning.

Pro-Tip: If the grass is extremely thick, mow it two weeks prior to chemical application to stimulate growth, then apply the herbicide once the grass has sprouted fresh, succulent green leaves.

Step 2: Mechanical Sod Stripping

Once the vegetation has died back, use a mechanical sod cutter to slice beneath the root zone. Set the blade depth to at least 2 inches to ensure you catch the deepest stolons.

1. Start at the perimeter of the infestation and work inward in straight, overlapping passes.
2. Roll the stripped sod into tight bundles for easy removal.
3. Dispose of the sod in green waste bins rather than a compost pile; St. Augustine is exceptionally hardy and can survive standard residential composting temperatures.

Step 3: Deep Soil Cultivation and Root Extraction

Sod stripping alone rarely removes 100% of the runner network. Use a rototiller to churn the soil to a depth of 6 inches. This exposes buried stolons that were missed by the sod cutter.

1. Rake the freshly tilled soil repeatedly to pull the white, fleshy stolons to the surface.
2. Collect and remove all organic debris.
3. If the infestation was severe, consider leaving the soil bare for an additional week to see if any dormant nodes sprout, allowing for a localized spot-treatment of remaining green growth.

Step 4: Final Site Stabilization

After the area is cleared of plant matter, improve the soil structure to prevent the re-emergence of unwanted grasses. Amend the soil with organic compost and establish new, desired vegetation or a landscape covering (mulch, fabric, or ornamental planting) immediately to occupy the ecological niche.

Common Site Failures and Field Fixes

• Root Regeneration: If new green shoots appear within 7 days of removal, the stolons were not completely extracted.
  
  
  • Actionable Fix: Use a targeted spot-treatment of herbicide on the new growth rather than tilling the entire area again.
• Herbicide Resistance or Poor Absorption: The grass remains green despite application.
  
  
  • Actionable Fix: The concentration was likely too low or the blades were too dusty/dormant. Increase surfactant usage and ensure the plant is adequately hydrated before the next application.
• Lateral Invasion: The grass is encroaching from an adjacent property.
  
  
  • Actionable Fix: Install a physical barrier, such as an HDPE plastic landscape edging, buried at least 6 inches deep to block subterranean stolons.

Frequently Asked Questions

Will weed-and-feed products kill St. Augustine?

No. Standard weed-and-feed products are designed to kill broadleaf weeds while leaving grasses intact. Because St. Augustine is a grass, these products will often encourage its growth rather than eliminate it.

Is solarization effective against St. Augustine?

Solarization using heavy-duty clear plastic can be effective in high-heat zones during peak summer months. However, it requires the area to be covered for 6 to 8 weeks, and the soil must reach temperatures exceeding 120 degrees Fahrenheit to kill the rhizome nodes.

Can I bury the removed sod?

Do not bury St. Augustine sod. The stolons are capable of growing through several inches of loose soil, and burying them simply provides a protected environment for the plant to propagate further. Always remove the debris from the site entirely.

How deep do St. Augustine roots go?

While the majority of the stolon network resides within the top 2 inches of soil, the fibrous root system can penetrate deeper depending on soil compaction. Thorough tilling is essential to ensure that segments of the root system are not left behind to initiate a new colony.

Contact our landscape specialists today to schedule an onsite soil audit and professional-grade eradication plan for your property. We ensure the complete removal of invasive turf species with industry-leading precision and site preparation.