A string trimmer picks up where a lawn mower leaves off, providing the finishing touches as it whisks away grass around trees and flower beds, straightens uneven edges along driveways, and trims patches of lawn your mower or tractor can't reach.

What's more, getting a capable trimmer needn’t mean spending $100 or more for a gasoline-powered model.

Several of the latest plug-in trimmers provide fine trimming and edging for less. But gas trimmers are still tops overall for tall grass and weeds. Faster starts for gas models, fewer tangles, and easier handling are among the other features you’ll find as manufacturers improve these tools.

WHAT’S AVAILABLE

Black & Decker, Craftsman (Sears), Toro, and Weed Eater are the major brands for electrics, while Craftsman, Homelite, Ryobi, Troy-Bilt, and Weed Eater are the big names in gas-powered models. Leading high-end brands include Bolens, Echo, Husqvarna, John Deere, and Stihl.

Corded electric trimmers. These cost the least and weigh about 5 pounds. Some perform comparably to gas models for most trimming. And all are quieter, create no exhaust emissions, require no tuneups, and start with pushbutton ease. But you’re limited by their power cord. Models with the motor at the bottom of the shaft tend to be harder to handle than those with the motor at the top, near the handle. You’ll also need hearing protection. And you’ll probably prefer a gas trimmer for tougher stuff. Price: $20 to $100.

Cordless electric trimmers. Battery-powered trimmers combine the freedom of gas trimmers with the easy starting, clean running, and minimal maintenance of corded electric models. They’re also the quietest overall. But they deliver relatively little cutting power and run only about 15 to 20 minutes before the onboard battery needs recharging, which can take up to a day. They also tend to be pricey and heavy for their performance (about 10 pounds). Price: $30 to $100 or more.

Gas-powered trimmers. These are the best choice for trimming far from an outlet. Many weigh less than before, though these 9- to 14-pound machines still outweigh corded models. Most have a two-stroke engine that starts more easily and runs more cleanly, though they still create exhaust emissions, require pull-starting and tuneups, and use a mix of gas and oil. Four-stroke models tend to run cleaner but add weight. And all require hearing protection. Price: $70 to $200.

IMPORTANT FEATURES

Curved shafts between the engine or motor and cutting lines are most common and can be easier to handle when trimming up close. Straight shafts tend to be better for taller users and when reaching beneath bushes and other shrubs. More come with a split shaft that comes apart to accept a leaf blower, edging blade, and other yard tools, though most add-ons aren’t very effective. A top-mounted motor eases handling for electric trimmers. Two cutting lines cut more with each revolution than one line. Most trimmers have a bump-feed line advance that releases line from a spool when you bump the trimmer head on the ground. A fixed-line head uses two fixed strips that are less convenient (you replace them as they wear) but eliminates jams and tangles. Gas trimmers usually include a choke and primer bulb for cold starting. Some use a three-step starting system for easier starts, and more have spring-assisted starting that reduces pulling effort. A centrifugal clutch allows a gas engine to idle without spinning the line—safer and more convenient than models where the line keeps turning. Electric-trimmer lines don’t spin until you press the switch. Some models make edging more convenient with a rotating head that swivels into the vertical position for edging. Heavy-duty models often have a shoulder harness to ease handling. Other conveniences include easy-to-reach switches, comfortable handles, and a translucent fuel tank.

HOW TO CHOOSE

Decide whether a gas-powered or electric trimmer fits your needs. Then keep these tips in mind:

See how it feels. While a lighter trimmer tends to reduce fatigue, weight isn’t the whole story. Good balance can be just as critical. Check it by adjusting the front handle for comfort and holding the trimmer in the cutting position with both hands; its weight should feel evenly distributed or slightly heavier at the top. Also check that controls are smooth and easy to reach.

Check the gap. Tall grass and weeds can slow a trimmer by wrapping around the top of its cutting head, especially if there’s a gap between it and the mounting for the grass-debris guard. Models with a smaller gap or a protective sleeve around the shaft tend to avoid the problem.

Consider your neighbors. If they’re close by, you may want to choose a quieter electric trimmer. If you opt for gas, wear hearing protection.

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