Dead St. Augustine grass presents a common challenge for homeowners seeking to restore a healthy lawn. Successful renovation requires completely removing the dead material before replanting or sodding the area. St. Augustine grass (Stenotaphrum secundatum) is a warm-season turfgrass known for its dense, creeping growth habit.
This horizontal growth is facilitated by thick, above-ground stems called stolons, or runners. Even when the blades are dead, these tough, fibrous stolons remain firmly anchored to the soil, making physical removal much more difficult than with bunch-type grasses. The extensive network of these stolons requires targeted strategies to fully clear the ground for new growth.
Initial Preparation for Removal
The process begins by clearly defining the perimeter of the affected area. Before starting physical work, equip yourself with safety gear, including sturdy work gloves, long pants, and eye protection. Gather necessary tools, such as a sharp rake, a low-set mower, and specialized cutting instruments.
Next, use a standard lawnmower set to its lowest possible cutting height to scalp the dead turf. This removes loose debris and reduces the bulk of the material, making the underlying stolon layer more accessible.
If using mechanical cutting tools, lightly moistening the soil a day before can be beneficial. Damp soil provides better lubrication for cutting blades and makes the dense root mass easier to slice through.
Mechanical and Manual Removal Methods
The most direct approach for removing large swaths of dead St. Augustine grass involves using a sod cutter. For extensive areas, renting a motorized sod cutter is recommended. It uses a reciprocating blade to slice the turf layer horizontally. The blade depth should be calibrated to one to two inches, ensuring it cuts just beneath the deepest stolon layer while minimizing topsoil removal.
Once the sod cutter passes, the dense turf layer separates from the ground and can be rolled or lifted away in manageable strips. These strips are heavy due to the interwoven root mass and retained soil. Cutting them into smaller sections simplifies lifting and disposal.
For smaller, isolated patches, manual removal with a flat-edged shovel or spade is a practical alternative. A sharp tool is necessary to cut through the fibrous runners and roots. Use the shovel to cut the dead turf into small squares or strips, making the sections easier to pry up.
The manual process requires significant physical effort due to the density of the St. Augustine root system. Apply downward pressure and use the shovel’s edge to sever the underlying roots, releasing the dead grass mat. Repeating this cutting and prying motion ensures the majority of the tough, dead stolons are lifted and removed.
Chemical Removal Options
Non-selective chemical options may be used to sterilize the soil surface, either after mechanical removal or as a primary method. Applying a broad-spectrum herbicide, often containing glyphosate, ensures that any remaining root fragments or stolons are killed. This is helpful if the dead grass was diseased, preventing the pathogen from infecting new turf.
Herbicide application must follow the manufacturer’s directions, paying close attention to the required waiting period before replanting. This interval allows the chemical to fully break down in the soil, preventing harm to new grass seed or sod. This period typically ranges from a few days to a couple of weeks, depending on the product and environmental conditions.
An alternative, non-chemical method for sterilizing the area is solarization, which uses concentrated heat to kill lingering roots and weed seeds. This involves wetting the exposed soil and covering the area with clear plastic sheeting, typically four to six millimeters thick. The plastic traps solar radiation, raising the soil temperature to lethal levels.
The edges of the plastic must be completely sealed by burying them in a small trench to maximize heat retention, creating a mini-greenhouse effect. For effective soil sterilization, the plastic should remain in place for a minimum of four to six weeks during the hottest part of the year.
Post-Removal Cleanup and Disposal
Once the dead turf has been physically cut and lifted, or killed chemically, thoroughly clean the exposed soil surface. Use a stiff-tined rake to gather small pieces of debris, loose stolons, or clumps of soil. This action also lightly aerates the uppermost layer of the soil, preparing it for renovation.
The removed dead sod strips and debris require proper disposal. Due to the density of St. Augustine stolons, the material decomposes slowly, making it unsuitable for a quick home compost pile unless heavily processed. The most straightforward method is bagging the material for municipal yard waste collection.
If composting is desired, the thick, fibrous stolons require shredding or chopping into very small pieces to accelerate decomposition. After the debris is cleared, the soil surface should be lightly smoothed and leveled. Using a rake or a landscaping board helps fill in minor depressions or remove small ridges, ensuring a uniform grade for future planting.