Lawn Care
How to Stop Cheater Grass from Invading Landscape Beds
The Anatomy of 'Cheater Grass' Invasions
In turf management, 'cheater grass' is not a single botanical species but a colloquial term for highly aggressive, stoloniferous, and rhizomatous grasses that bypass physical boundaries to invade ornamental beds, hardscapes, and adjacent turf. The primary culprits include Bermudagrass (Cynodon dactylon), Torpedograss (Panicum repens), and Kikuyu (Pennisetum clandestinum). These grasses 'cheat' their way into unwanted areas using two distinct vectors: above-ground stolons that creep over mulch and edges, and below-ground rhizomes that tunnel beneath shallow landscape borders.
According to the Clemson University Home and Garden Information Center, Bermudagrass rhizomes can penetrate up to 8 inches deep in standard soils, but in sandy substrates or during drought conditions, they will push downward to 18 inches or more seeking moisture. Eradicating these grasses requires a multi-layered maintenance protocol combining deep physical barriers, selective chemistry, and precision edging.
Step 1: Excavation and Physical Barrier Installation
Standard 4-inch plastic landscape edging sold at big-box stores is entirely ineffective against cheater grass. Rhizomes will easily tunnel beneath it, and stolons will bridge over it within a single growing season. To establish a permanent physical defense, you must install a deep, rigid root barrier.
- Trench Excavation: Using a mechanical trencher or a flat spade, dig a continuous trench along the perimeter of the landscape bed. The trench must be 6 inches wide and a minimum of 24 inches deep. For Torpedograss, increase the depth to 30 inches.
- Rhizome Removal: Before placing the barrier, manually sift through the excavated soil and trench walls using a Hori-hori knife to extract all existing white, fleshy rhizomes. Leaving even a 2-inch fragment behind will result in a new plant.
- Barrier Placement: Insert 60-mil to 80-mil High-Density Polyethylene (HDPE) panels into the trench. Ensure the top edge of the barrier extends exactly 1/2 inch above the final grade level to prevent stolons from growing over the top.
- Seam Sealing: Cheater grass will exploit the microscopic gap where two barrier panels meet. Overlap panels by 4 inches and seal the joint using double-sided butyl flashing tape or mechanical aluminum joiner strips.
- Backfilling and Compaction: Backfill the trench with native soil, tamping it down every 4 inches with a hand tamper to eliminate air pockets that rhizomes could exploit for lateral movement.
Root Barrier Material Efficacy Matrix
| Material | Thickness / Gauge | Lifespan | Cost per Linear Foot (2026) | Efficacy Against Rhizomes |
|---|---|---|---|---|
| HDPE Plastic | 60-mil to 80-mil | 20+ years | $2.50 - $4.00 | Excellent (when seams sealed) |
| Corrugated Aluminum | 0.032 inch | 30+ years | $5.50 - $7.50 | Superior (impenetrable) |
| Fiberglass | 1/4 inch | 15 years | $3.00 - $4.50 | Good (prone to cracking) |
| Poured Concrete | 4 inches wide | 50+ years | $12.00 - $18.00 | Absolute (structural) |
Step 2: Selective Chemical Eradication in Ornamental Beds
Once physical barriers are in place, you must address the cheater grass that has already established inside the ornamental beds. You cannot use non-selective herbicides like glyphosate here without killing your desirable broadleaf plants. Instead, rely on post-emergent graminicides (grass-specific herbicides).
The industry standard for selective control in landscape beds is Fluazifop-P-butyl (commonly sold as Fusilade II or Ornamec). This active ingredient targets the ACCase enzyme specific to grasses, leaving broadleaf ornamentals, hostas, and daylilies unharmed.
Application Protocol for Fluazifop-P-butyl:
- Rate: Mix 0.5 to 0.75 fluid ounces of product per 1,000 square feet.
- Adjuvant: You must include a Non-Ionic Surfactant (NIS) at a rate of 0.25% v/v (roughly 1/2 teaspoon per gallon of water) to ensure the chemical penetrates the waxy cuticle of the cheater grass.
- Timing: Apply when the invasive grass is actively growing and between 4 to 8 inches tall. Do not apply during summer drought stress, as the grass will not translocate the herbicide to its roots.
- Follow-up: A second application is almost always required 14 to 21 days after the initial spray to catch late-germinating shoots.
Step 3: The Rope-Wick Technique for Turf Borders
When cheater grass invades an adjacent desirable turf area (e.g., Bermudagrass invading a Tall Fescue lawn), selective herbicides are often ineffective because both are grasses. Broadcast spraying glyphosate will destroy the entire lawn. The solution is a mechanical wick application.
A rope-wick applicator consists of a reservoir filled with herbicide that feeds into a porous cotton or fiberglass rope. As you drag the rope over the turf, it deposits the chemical only on the taller blades it contacts.
Critical Mowing Requirement: For the wick technique to work, you must mow the desirable lawn at its lowest recommended height, then allow the cheater grass to grow until it is exactly 2 to 3 inches taller than the desirable turf. The wick must only touch the invasive grass; if it brushes the desirable turf, you will cause severe phytotoxicity and turf death.
Fill the wick reservoir with a 33% solution of 41% Glyphosate (1 part glyphosate to 2 parts water). Walk backward at a steady pace of 2 miles per hour, dragging the wick in a single direction. According to the University of Minnesota Extension, wiping the weed twice in opposite directions increases kill rates by up to 40% compared to a single pass, but increases the risk of dripping onto desirable turf.
Step 4: Ongoing Vertical Edging Protocols
Physical barriers and chemicals will fail if you do not maintain a strict vertical edging schedule. Cheater grass stolons can bridge a 6-inch mulch gap in as little as 10 days during peak summer growth.
- Frequency: Edge turf borders every 14 to 21 days when soil temperatures at a 2-inch depth exceed 70°F.
- Tool Selection: Use a steel half-moon manual edger or a motorized stick edger equipped with a minimum 4-inch steel blade. Avoid plastic rotary trimmer blades, as they tear the stolon rather than severing it cleanly, which can stimulate lateral branching.
- The 'V-Trench' Method: Do not just cut a straight vertical line. Cut a 45-degree angle away from the turf to create a shallow V-trench. This exposes the severed stolons to air and sunlight, desiccating them before they can root into the adjacent bed.
- Debris Removal: Always rake out the severed stolons from the V-trench. If left in the trench, they will decompose and create a soil bridge that new stolons will use to cross the gap.
Frequently Asked Questions
Can I use landscape fabric to stop cheater grass?
No. Woven and non-woven landscape fabrics are designed for weed seed suppression and water permeability, not rhizome blocking. Aggressive grasses like Bermudagrass will easily pierce standard 3oz/sqyd landscape fabrics within a single season. Furthermore, once the grass weaves through the fabric, manual removal becomes impossible without destroying the fabric and the root systems of your desirable plants.
Will solarization kill cheater grass rhizomes?
Solarization (covering the soil with clear 4-mil polyethylene plastic for 4 to 6 weeks during peak summer) is highly effective at killing weed seeds and shallow fungal pathogens. However, it is largely ineffective against deep rhizomatous cheater grass. The heat rarely penetrates deep enough to kill Torpedograss or Bermudagrass rhizomes located below the 6-inch mark. It will burn off the top growth, but the grass will aggressively regenerate once the plastic is removed.
How much does professional cheater grass remediation cost?
As of 2026, professional landscape contractors typically charge between $8.00 and $14.00 per linear foot for complete trenching, rhizome extraction, and 60-mil HDPE barrier installation. For a standard 50-foot landscape bed border, expect to pay between $400 and $700 for a permanent physical barrier solution, excluding the cost of selective chemical applications.
