How to Kill Weeds in Your Lawn

A weed-free lawn rarely comes without effort. Weeds, which are basically any type of broad-leaf plant or grass you don't want growing in your lawn, will take over when not managed. The creep can be slow at first, almost unnoticeable, before you get a chance to take stock of the problem. Methods for killing weeds in your lawn range from the nontoxic, but labor-intensive hand weeding method to carefully targeted and applied herbicide applications.

Two types of weeds commonly invade lawns: grass-type weeds and broad-leaf perennial weeds.

Crabgrass (Digitaria spp.), an annual grass that takes over lawns by slowly crowding out lawn grass. 

Goosegrass (Eleusine indica), an annual grass with flat stems that grows in clumps. Also called wiregrass.

Foxtail (Setaria spp.), an annual weedy grass with flat-leaf blades and large seed heads.

Dandelions (Taraxacum officinale), the common yellow- flowering weeds seen all over unkept lawns. These perennials, which grow in U.S. Department of Agriculture zones 3 through 9, have deep taproots. 

Broadleaf plantain (Plantago major), a low-growing broad-leaf weed hardy in USDA zones 3 through 10. 

Hand weeding is an effective, nontoxic way to kill weeds in the lawn. Use a dandelion knife -- a narrow weeding tool designed to dig out dandelion taproots -- to dislodge perennial weed roots. If you leave root parts in the soil, some weeds will just regrow from the root. A dandelion knife is also effective for sliding under weedy grasses. Early in the season, or as soon as the weeds appear, is the best time to weed by and. Make sure to get dandelions and other flowering weeds before they go to seed or your task will be doubly hard next near.

Hand weeding is most effective if you do it regularly. Pull weeds as soon as they appear. Once weeds take over large areas of the grass, hand weeding is a daunting and time-consuming task.

Look for a herbicide that contains 2, 4-D along with dicamba to target a range of broad-leaf lawn weeds. For weedy grasses, look for a product that also contains quinclorac. You can find herbicides that contain a combination of these ingredients to control both broad-leaf weeds and weedy grasses at the same time. These ingredients should be listed on the front of the label, typically in the lower left-hand corner. Use herbicides to spot-spray the affected area rather than spraying the whole lawn area. Spray in the spring and early summer when weeds are actively growing. Wait for a dry day with temperatures between 45 and 90 degrees Fahrenheit.

Rubber gloves 

Long pants

Long-sleeve shirt 

Socks and shoes

Safety goggles 

1-gallon hand-held sprayer

Put on long sleeves, shoes and socks, safety goggles and rubber gloves before starting.

Before spraying any weed-control chemical on lawn grass, make sure the product is safe for your lawn. Not all herbicides are safe for all lawn types.

Mix 1 to 2 ounces of concentrated herbicide with 1 gallon of water in a 1-gallon sprayer. This is enough to cover a 500-square-foot area.

You can skip the mixing step by buying a ready-to-use product. These typically come with a sprayer nozzle attached.

Spot-spray weeds in the lawn until the leaves are damp but not dripping. Avoid using so much that the herbicide pools or puddles around the weed.

Spray again 14 days after first application. This helps target and eliminate weeds like dandelions, crabgrass and foxtail. Do not use more than twice a year.

Wait to mow the lawn for at least two days after spraying weeds, and make sure the clippings go in the garbage, not in the compost or mulch pile.

Wait four weeks before reseeding the area after spraying herbicides.

Stay off the treated areas and keep pets and children away until the area dries completely. If you get any herbicide on your skin, wash it off right away with soap and water. Discard all used empty product containers in the garbage. Never reuse herbicide containers for any reason.