Trimmers and techniques to keep your grass looking its best
String trimmers, which cut greenery with whirling plastic lines, can trim right up to trees, steps, and rocks. They're great for maintaining a neat edge along walks and beds, and they can tidy a rocky hillside that's too irregular to mow. Many can also accept a metal blade for leveling tough scrub and small saplings.
Roger Cook, This Old House landscape contractor, keeps two trimmers in his truck—one with plastic string, the other with a blade. He switches to the latter the minute the string stops cutting and wraps around a tough stem. String comes in a range of thicknesses and textures, but you're limited by what your machine can accept. "In most cases, heavier is better," says Roger. "The right texture, on the other hand, depends on your landscape. You have to experiment."
The trimmers themselves come in two basic varieties: the more costly and powerful gas models (2-cycle or 4-cycle engine, the latter up to $350) and the economical electric (cordless or corded, some less than $50). The right choice depends on the property's size, its terrain, and your tolerance for noise and pollution. Keep in mind: Trimmer tips spin at close to 400 mph, so don't forget eye and ear protection, as well as boots, long pants, and gloves. And stay clear of outdoor wiring, lest you zap yourself instead of the weeds.
Pros: Power to clean up a big yard, large cutting swath (16 to 18 inches)
Cons: Weight, noise, pollution, maintenance; the need to keep gas and oil on hand
For an affordable trimmer (under $200) with the power and the reach to clean up a large yard, look for a 2-cycle machine that has separate primer, choke, and throttle controls for easy starting. Two-cycle engines run on a mix of gas and oil.
Similar to shown: A curved shaft that's easier on the back, with a loop handle for better balance and control. Echo GT-225 curved shaft trimmer; about $160; shop.echo-usa.com
With a big jungle to tame, you'll want a trimmer with a 4-cycle engine. Though more expensive ($300 and up), these powerful machines are easier to start, quieter, pollute less, and run smoother than 2-cycle motors, and don't require a gas-oil mix.
Shown: A common straight shaft, which is more durable—and versatile in the attachments it accepts. Honda HHT25S; about $350; hondapowerequipment.com
For flattening brush and saplings with a brush-cutting blade, you need the control of bicycle-style handlebars, especially if a hearty trunk kicks the head back at you. Handlebars can be fitted to most gas-powered trimmers; however, they are less maneuverable for string edging.
Shown: A 4-cycle brush-cutting package, with handlebars, blade, and shoulder straps. Husqvarna 326RJX; about $390; husqvarna.com
Typically, trimmer string comes wound around the head and is slowly eaten away with use. Some heads release more string automatically; others you tap on the ground. Eventually, when the spool is empty, you have to stop and wind a new one.
Check out Echo's Rapid-Loader trimmer head (left), which has locking clips that hold short pieces of plastic string. When it's time to replace them, you just pull out the old line and slide in the new—no winding necessary. Roger loves them. "I keep a handful of strings in my pocket," he says. "Within 30 seconds, I can have new ones on and I'm off to work again."
Pros: Portability and light weight; low price ($50 to $150); less noise
Cons: Less power; limited extension-cord reach or battery life; small cutting swath (12 to 15 inches); can't handle brush cutting
While not able to saw brush, a 3-amp or better corded electric machine is powerful enough to clean up a suburban yard, provided you've got outdoor outlets and a long extension cord. Plus, it's the least expensive option.
Similar to shown: Toro electric string trimmer; about $40; amazon.com
Cordless trimmers can handle grass and weeds in a small yard, and they're easy to toss in the trunk when it's your turn to tidy Grandma's patio. The rechargeable 12-volt battery means no hassling with extension cords or gas-oil mixtures, and purchasing a spare battery pack will alleviate the disadvantage of the short run time.
Similar to shown: Black & Decker cordless string trimmer; about $150; blackanddecker.com
For rocky and hilly acreage, consider a 4-cycle, two-wheel trimmer/mower. It will cut grass like a rotary mower without the shriek of metal blades scalping rocks, and because the string head sits way out in front, it trims right up to posts and walls. The disadvantages are price (starting at $450) and the fact that you can't flip it up on edge for maintaining a crisp border around beds and walks, as you can with a regular string trimmer.
Shown: DR trimmer/mower Spint line; about $550; countryhomeproducts.com
A string trimmer can strip a lawn bald if held too close to the surface. Keep the string head about 2 to 3 inches off the ground, just like a mower blade, and sweep the machine side to side in a steady motion parallel to the ground. Don't worry if you don't get it right the first time; we all make mistakes, and it will grow out—just like a bad haircut.
If you trim tall grass and weeds at ground level, the stems are liable to tangle around the trimmer head and stall it. Roger's solution is to trim tall weeds from the top down, so the string chomps them into little pieces. For big fields of grass, consider getting a special grass-cutting head that has three plastic blades designed to lay the stems down flat without tangling the mechanism.
Once you've established a clean edge along driveways, walks, and flower beds, you can maintain it with your trimmer. Just shift your grip so the string spins vertically, like an airplane propeller. It will track right along the bed line and make hash of any sideways-growing grass.
A string trimmer can get right up to tree and shrub trunks, fence posts, and concrete steps. But be careful to stop short of hitting these with the string. You can kill a tree by stripping its bark, or cut a chunk out of wood or concrete. Approach these fixtures gingerly, and pull back as soon as you hear or feel the distinctive click of slapping string. (Or better yet, create mulch beds around trees and posts so you never have to get close.)
When you switch to a metal blade for cutting brush and saplings, protect yourself with long pants, helmet, boots, and goggles or a face mask, plus shoulder straps to keep you from getting an aching back. Never remove the blade guard: It not only protects you, it also keeps the blade from wreaking havoc on rocks, walks, or posts.
With any trimmer, wipe off bits of grass and debris when you stop for the day, and check both the gas level and what's left on the string reel. Neatly coil the cord or recharge the batteries on electric machines. Some gas machines must be stored upright or level so fluids don't leak; check your manual.