Lawn scalping is a specific lawn maintenance practice involving cutting the grass at the lowest possible mower setting once a year. The primary goal is to clear out this dead material, often referred to as thatch, to prepare the turf for the active growing season. By getting rid of the tall, brown canopy, sunlight can reach the soil surface, warming it more quickly and stimulating a faster, more vigorous green-up of the new grass shoots.
Identifying Grasses That Require Scalping
Scalping is a technique reserved almost exclusively for warm-season grass varieties that enter a state of winter dormancy. Common examples include Bermuda and Zoysia grasses, which spread aggressively via both above-ground stems (stolons) and below-ground stems (rhizomes). This growth structure allows them to tolerate the stress of a severe cut and quickly recover once the weather warms up. The practice helps manage the thick, matted layer of dead turf that these grasses accumulate during their dormant phase.
Other warm-season grasses like St. Augustine, Centipede, and Buffalo grass are generally not good candidates for severe scalping because their growing points are located higher up on the stolons. Cutting these varieties too low can severely injure the plant, leading to turf death. Conversely, cool-season grasses such as Kentucky Bluegrass and Fescue should never be scalped. These grasses do not go fully dormant and rely on their leaf surface for energy production throughout the year, meaning aggressive removal of the green blades will deplete their energy reserves and encourage weed growth.
Optimal Timing for Scalping
The correct time to scalp is not a fixed calendar date but is determined by the grass’s biological state and the local climate. The timing is centered on the moment just before the grass naturally breaks dormancy and begins its spring growth cycle. The turf must still be completely brown or mostly brown from its winter rest.
A reliable environmental indicator is the soil temperature, which should be consistently reaching a range of 55 to 60 degrees Fahrenheit. This temperature signals that the roots of warm-season grasses are preparing to become active. Scalping at this specific point allows the newly exposed soil to absorb more solar energy, which accelerates the soil warming process and results in an earlier spring green-up.
It is important to ensure that the threat of a hard freeze or prolonged frost has passed before scalping. Scalping too early exposes the grass crowns and rhizomes to potential cold damage, which can injure the plant. Conversely, waiting too long until the grass is already actively growing and showing a strong green color will cause significant stress and shock to the new, tender growth because the plant will have already invested energy into the new shoots, and removing them interrupts the early-season growth cycle.
Step-by-Step Scalping Technique
Preparation is necessary before the scalping process begins, including sharpening the mower blades to ensure a clean cut that minimizes tearing and reduces the risk of disease. The aggressive cut should not be performed in a single pass, especially if the grass is tall or dense. Instead, the mower height should be gradually reduced over several mowing sessions to remove the bulk of the material without violating the one-third rule on the final pass.
For Bermuda and Zoysia turf, the final scalping height is typically between 0.5 inches and 1 inch, with higher-quality turf often cut lower. The goal is to set the mower to its lowest setting without digging into the soil. Mowing in multiple directions, such as a north-south pattern followed by an east-west pattern, helps ensure the entire area is cut evenly and all the dormant material is removed.
All the resulting grass clippings—the brown, dead material—must be collected and removed from the lawn surface. Unlike regular mowing, this debris cannot be left behind to decompose because it will smother the new growth and significantly contribute to thatch buildup. This collected material should be bagged or raked up and can be added to a compost pile or disposed of as yard waste.