A string trimmer is a versatile tool that can handle both trimming grass in tight spots and edging along sidewalks, driveways, and garden beds. While a dedicated power edger is designed specifically for cutting clean vertical edges, many homeowners use a string trimmer for edging by rotating the head or adjusting their technique. This guide focuses on using a string trimmer safely for lawn edging, drawing on manufacturer safety instructions and expert gardening advice.
String Trimmer vs. Dedicated Edger: Understanding the Roles
A string trimmer cuts grass and light weeds with a flexible nylon line that spins at high speed. When turned on its side, it can cut a vertical edge along a hard surface or garden border. A dedicated power edger uses a metal blade to slice into the soil and create a crisp separation. Both tools have their place, but a string trimmer offers the advantage of doing two jobs with one machine. For more on the range of tools available, see our edging tools section and the lawn edging tools overview.
Safety Rules from the EGO String Trimmer Manual
The operator’s manual for the EGO ST1510T string trimmer provides detailed safety instructions that apply to many cordless trimmers. While your own model may differ, the core principles are widely shared. Always consult the manual that came with your tool before use.
Read the Manual First
EGO’s manual states that the user must read and understand the operator’s manual before using the product to reduce the risk of injury. It warns that failure to follow all instructions may result in electric shock, fire, or serious personal injury.
Wear Proper Eye and Ear Protection
The manual emphasizes eye protection that meets the ANSI Z87.1 standard. It recommends safety goggles or safety glasses with side shields, and a full face shield when needed. It also lists hearing protection as part of the personal protective equipment that should be used for appropriate conditions.
Keep Bystanders and Pets Away
EGO instructs operators to keep children and bystanders away while the tool is running. Distractions can cause loss of control, and thrown debris can injure anyone nearby. The manual does not specify a minimum distance, so a generous buffer zone is wise.
Do Not Use in Rain or Wet Conditions
The manual warns against using the appliance in damp or wet locations. It also states that the battery pack should not be charged in rain or wet locations. Operating a string trimmer in wet grass or during rain increases the risk of electric shock and slipping.
Keep the Guard in Place
EGO’s safety instructions say to make sure all guards and safety devices are properly and securely attached before use, and never operate without guards in place. The guard helps deflect debris and protects the user from the spinning line.
Use Only Nylon Line
The manual explicitly warns against using wire, metal-reinforced line, or any material other than nylon cutting line. It states that pieces could break off and be thrown at high speed. When replacing line, use only nylon line up to 0.095 in. (2.4 mm) in diameter, as heavier lines can overload the motor and cause overheating.
Inspect the Tool Before Each Use
EGO advises that if the tool starts to vibrate abnormally or becomes noisy, stop the motor and check immediately for the cause. A cracked, damaged, or worn-out cutting head should be replaced right away, even if the damage appears superficial, because such parts can shatter at high speed.
Edging Technique and Regular Maintenance
The Royal Horticultural Society (RHS) offers practical advice for keeping lawn edges neat. While their guide focuses on manual edging shears, the principles of regular trimming apply equally when using a string trimmer.
The RHS recommends trimming lawn edges after each time you mow the lawn. During peak growth, this may be as often as once a week. Regular trimming prevents grass from creeping into borders and keeps edges looking crisp. When using a string trimmer for edging, hold the tool so the line cuts vertically along the edge. Move slowly and overlap your passes slightly to avoid missed tufts. After trimming, rake up the clippings or flick them into the border to decompose.
For a well-defined edge, the RHS suggests redefining the border with a half-moon edging tool once a year. This creates a drop of about 7.5 cm (3 in) from the lawn to the border, which helps keep plants off the grass and grass out of the bed. If you are installing new edging materials, visit our installation guides for step-by-step instructions. For seasonal care tips, see lawn maintenance.
Pre-Edging Checklist for Safe Operation
Before you start the trimmer, run through this checklist based on the EGO manual’s safety points:
- Read the manual: Understand all controls and safety features.
- Eye protection: Put on safety glasses or goggles that meet ANSI Z87.1.
- Hearing protection: Wear earplugs or earmuffs if the trimmer is loud.
- Clothing: Wear long pants, sturdy non-skid shoes, and avoid loose items that could catch in moving parts.
- Guard check: Confirm the debris guard is securely attached and undamaged.
- Line check: Use only nylon line of the diameter recommended by the manufacturer. Never use wire or metal-reinforced line.
- Cutting head: Inspect for cracks or wear; replace if damaged.
- Work area: Clear the area of sticks, stones, and debris that could be thrown. Ensure children and pets are at a safe distance.
- Weather: Do not operate in rain or wet conditions.
- Battery: If cordless, ensure the battery is fully charged and properly seated. Do not charge in wet locations.
Frequently asked questions
Can I use a string trimmer as an edger?
Yes, many string trimmers can be turned on their side to cut a vertical edge along pavement or garden beds. While a dedicated power edger may produce a cleaner cut in tough soil, a string trimmer is a practical alternative for regular maintenance. Always check your trimmer’s manual for edging instructions specific to your model.
What personal protective equipment do I need for string trimmer edging?
The EGO manual specifies eye protection meeting ANSI Z87.1 and recommends hearing protection, a dust mask, non-skid safety shoes, and long pants. Avoid loose clothing and tie back long hair. Sturdy footwear and gloves add extra protection.
How often should I trim my lawn edges?
The Royal Horticultural Society advises trimming edges after each mowing session. During the growing season, this may be weekly. Regular trimming keeps edges neat and reduces the effort needed for each session.
For more detailed guidance on using a string trimmer for edging, visit our Edging with String Trimmers category page.
