Bermuda grass is an aggressive, warm-season turf known for its dense growth habit and tolerance for frequent, low mowing. Homeowners often use a practice called “topdressing,” which involves spreading a thin layer of material over the existing turf. This maintenance technique aims to improve the lawn’s surface and underlying soil conditions.
How Sand Affects Root Health and Drainage
Sand does not provide nutritional value to the grass, but its benefit lies in improving the physical structure of the soil. When applied correctly, sand increases the pore space within the soil, which allows for better air and water exchange. This structural improvement is particularly effective in lawns with heavily compacted or clay-based native soil.
Bermuda grass thrives in well-drained, oxygenated environments. Sand helps create this ideal root zone by increasing pore space, which prevents waterlogging and ensures oxygen reaches the roots. This improved aeration and drainage supports a robust root system, making the turf more resilient to drought and heat stress. The ideal soil texture for Bermuda grass is a sandy loam, often composed of about 60% sand.
Using Sand for Lawn Leveling
One of the primary reasons homeowners apply sand to Bermuda grass is to correct surface irregularities and achieve a smooth lawn. Bermuda grass is unique among common turf types because its vigorous growth rate allows it to quickly grow through a thin layer of material without being smothered. This characteristic makes it well-suited for a leveling application.
Sand is spread into low spots, dips, or uneven areas caused by foot traffic, settling, or winter damage. Sand is preferred over topsoil for leveling because it breaks down much slower, providing a more permanent fix to the surface contour. Apply the sand in very thin layers, generally no more than 0.5 inches at a time, and then work it into the turf canopy with a leveling rake or drag mat.
This mechanical application smooths the surface, which is beneficial for aesthetics and maintenance, especially when mowing at a low height. Multiple light applications over a growing season or multiple years are more effective than a single heavy application. After spreading, the grass stolons quickly grow new roots into the sand layer and push new leaves through, restoring a uniform, level plane.
When Sand Damages Bermuda Grass Growth
Improper use of sand can unintentionally damage Bermuda grass growth through two primary mechanisms: nutrient dilution and the creation of distinct soil layers. Since sand lacks organic matter and nutrients, excessive application dilutes the existing topsoil. This dilution effectively starves the grass unless fertilization is increased to compensate for the reduced nutrient-holding capacity.
Layering is a significant problem that occurs when the applied sand differs drastically in particle size from the native soil. For example, placing coarse sand over fine-textured clay or silt-heavy soil impedes water movement.
This layering can create a “perched water table,” trapping water above the interface, or it can form a hydrophobic barrier. Both conditions hinder root growth, cause root suffocation, and lead to poor grass health. To mitigate this risk, use sand similar to the existing soil or use a screened topdressing mix that includes compost.