Lawn leveling, often called topdressing, involves spreading a thin layer of material over the turf to correct surface irregularities. The main goal is to eliminate minor dips and bumps that create an uneven mowing surface, preventing scalping the grass blades in high spots. Leveling also improves water drainage by preventing pooling in low areas, which can suffocate roots and foster disease. By smoothing the terrain, this practice promotes a healthier, denser lawn that is safer and easier to maintain.
Recommended Leveling Mixes and Ratios
The material chosen for leveling directly impacts the lawn’s long-term health, making a mixture preferred over a single component. The ideal blend incorporates coarse sand, screened topsoil, and fine compost to balance drainage, structure, and nutrient content. Coarse, washed river sand provides the structural backbone, filling low spots and improving water percolation. If the existing soil is heavy clay, increasing the sand content prevents a hard, layered boundary from forming.
Screened topsoil contributes volume and mineral content, but it must be finely sifted to avoid introducing clumps or debris that could smother the grass. Topsoil ensures the mixture is compatible with the underlying soil structure, promoting root integration. Compost, typically well-aged, is incorporated for organic matter, enhancing the soil’s water-holding capacity and introducing beneficial microorganisms.
A common starting point is a 50:50 ratio of sand to screened topsoil, balancing structure and nourishment. For lawns with poor soil or compaction, a three-part blend (40% sand, 40% topsoil, 20% compost) is often recommended. If the existing soil is already sandy, increasing the compost and topsoil percentage helps retain moisture and nutrients better. The final ratio should always be adjusted to complement the existing soil composition and address specific drainage needs.
Essential Preparation Steps Before Leveling
Proper preparation ensures the leveling material reaches the soil surface and allows the grass to recover quickly. The first step is scalping the lawn by mowing the grass to an extremely short height (0.5 to 1.5 inches). This low cut exposes the ground’s contours, making it easier to identify and fill low spots accurately. All resulting clippings must be removed to prevent a smothering layer beneath the leveling mix.
Next, assess the thatch layer, the accumulation of organic matter between the grass blades and the soil surface. If this layer is thicker than half an inch, dethatching is necessary so the leveling mix can reach the soil. Following mowing and debris removal, core aeration is recommended, especially for compacted lawns.
Core aeration involves pulling small plugs of soil from the ground, relieving compaction and creating pockets for the leveling mix to fall into. This helps integrate the new material with the native soil, improving root growth and drainage. Leveling should only be done when the grass is actively growing and can quickly push new blades through the material. For cool-season grasses, this is usually late summer or early fall; warm-season grasses respond best in late spring or early summer.
Spreading and Working the Material
Once the lawn is prepared, distribute the leveling mix across the area in small piles. Apply the material in thin layers, never exceeding one-half inch of depth at one time, as a thicker application will suffocate the turfgrass. For depressions deeper than one inch, fill them incrementally over several applications, allowing the grass to grow through each layer before adding the next.
The material is then spread and worked into the turf canopy using a specialized lawn leveler, a landscape rake, or a drag mat. The lawn leveler (a wide, flat metal grid) is the most efficient tool for dragging the material back and forth, forcing the mixture down and evenly distributing it. A push broom or the back of a garden rake can be used for smaller areas or a final sweep to help the grass blades stand upright.
After the mix is spread, a light watering is immediately necessary to settle the material and help it filter down to the soil level. This prevents the loose material from being displaced by wind and eliminates air pockets. For the next one to two weeks, water the lawn frequently and lightly to keep the top layer moist, encouraging rapid grass growth. Once the grass blades have grown through the layer, return to a regular, deep watering schedule.