The question of when to use a string trimmer, often called a weed eater, is a common dilemma for homeowners seeking a manicured lawn. This tool cuts grass and weeds in areas a standard lawnmower cannot reach, such as around fence posts, trees, and along foundations. The sequence of these two tasks—mowing the main lawn and trimming the perimeter—significantly impacts the final appearance and efficiency of yard maintenance. Adopting the correct order ensures a clean, professional look that unifies the yard.
The Definitive Answer: Trimming Before Mowing
For maximum efficiency and the highest quality finish, string trimming should almost always be completed before the lawnmower is brought out. This sequence ensures the mower becomes an integral part of the cleanup process, saving considerable time. The logic behind this approach centers on two factors: achieving uniform grass height and simplifying debris management.
Trimming around obstacles first allows you to cut the taller perimeter grass down to the same height the lawnmower deck is set to achieve. If you trim after mowing, it is difficult to visually match the height of the already-cut lawn, often leading to noticeable, uneven patches around structures. Trimming first establishes a consistent grass canopy across the entire yard area.
The second benefit is that the lawnmower acts as a mobile vacuum for the trimmings. When you cut the long grass with the string trimmer, the clippings fall directly onto the main lawn area. The subsequent pass with the mower then mulches these loose clippings or deposits them into the bagging system. This eliminates the need for extensive raking or blowing, which would be necessary if trimming occurred after mowing.
Mastering the Technique: Achieving the Perfect Trim Height
Achieving a seamless transition from the main lawn to the trimmed edges depends on holding the trimmer correctly to match the intended mower height. The string trimmer head must be held horizontally, parallel to the ground, allowing the cutting line to shear the grass blades evenly. This avoids the common mistake of “scalping,” which occurs when the trimmer line digs into the soil and rips out the grass, causing dead patches.
When trimming against an obstacle like a fence or wall, the operator should walk slowly and methodically, using the string line’s tip to cut only the exposed grass. For areas with tall or thick grass, start the cut from the top of the stalks and work downwards in layers. This prevents the trimmer line from getting bogged down and ensures a cleaner, more controlled cut.
The goal is to blend the grass near the edge with the rest of the lawn, a process known as tapering. This gradual reduction in height creates a softer visual line than a vertical cut. Proper execution ensures the final mowed grass line is indistinguishable from the trimmed sections, unifying the entire lawn surface.
The Cleanup Advantage and Edging Distinction
Following the “trim first” method streamlines cleanup, leaving only minor debris to manage. After trimming and mowing, the final step involves using a leaf blower to clear residual clippings from hard surfaces like sidewalks and patios. This final pass ensures that the clean lines created by the cutting process remain visible and free of loose material.
It is important to differentiate between string trimming and power edging, as the terms are often confused. String trimming uses a flexible nylon line to cut horizontally, blending the grass height near obstacles. Conversely, a power edger utilizes a vertical metal blade to create a clean, sharp cut along hardscape borders, separating the lawn and the pavement.
While the string trimmer can be angled for a less precise form of edging, the dedicated edger produces a more professional result along sidewalks and driveways. By completing all trimming and edging before mowing, the final pass with the blower removes the accumulated debris from all cutting processes simultaneously. This three-step flow—trimming/edging, mowing, and then blowing—is the most time-efficient method for a professional-grade lawn finish.