Buying Guide

Best Weed Killer for Your Yard

Types of Weed Killers
A group of dandelions, a common weed.

Weed killers contain chemicals that kill plants or inhibit their normal growth. The best weed killer depends on what types of weeds you are trying to eradicate. Herbicides vary according to their effects – some aim to kill weed seedlings while others kill weeds after they are up and growing.


There are four basic characteristics that describe how all herbicides work: emergence, selectivity, persistence and translocation. Understanding the importance of each characteristic will help you read product labels and properly select the best weed killer for your yard. 


Emergence

Weed killers are either pre-emergence, which target germinating seedlings before they grow, or post-emergence, which work on weeds that are already experiencing growth. Apply pre-emergent two to three weeks before the weeds germinate and apply post-emergent to the leaves of the plant. 


Selectivity

Weed killers are either selective, which kill weeds without damaging nearby beneficial plants, or non-selective, which generally kill all plants in the vicinity of application. Use a selective herbicide to kill dandelions without damaging your lawn, and a non-selective herbicide to kill weeds growing in sidewalk cracks. 


Persistence

Persistence describes how long the herbicides remain active after application to provide ongoing weed control. Those that provide no lasting prevention of weed growth are called non-persistent. Those that kill everything and prevent regrowth are persistent. 


Translocation

Translocation refers to how the plant’s xylem and phloem circulate materials through its system. Translocated herbicides work their way through a plant’s internal system to break it down, while contact herbicides kill plants on contact. 

How to Kill Weeds in Lawns
A person using weed killer for lawns.

Treating weeds springing up in your lawn is tricky – you want to eliminate the weeds but keep the grass lush and undamaged. The best weed killer for lawns will be a weed control product that has been specifically designed for use in lawn care.


Apply weed prevention products to your lawn in early spring or late summer before weeds germinate. Many of these can be applied using a spreader for full lawn coverage. Weed killers that eliminate dandelion, clover, crabgrass and nutsedge should be applied when these types of weeds are actively growing in the late spring or late summer. 

How to Kill Weeds in Gardens
A person sprinkling granulated weed killer to kill weeds in a garden.

When a weed appears in your landscape beds, including mulched tree rings, you must kill it quickly to prevent it from spreading. But be mindful not to harm surrounding plants or damage the soil so it cannot nourish future plants you may want to grow.


Pre-emergent control products stop weed seeds from sprouting – check the label for a list of specific weeds. Apply before the weeds germinate in early to late spring for best results.


A post-emergent control product is typically non-selective and will help you kill both grassy and broadleaf weeds quickly. When applying, be careful to avoid any desirable plants as a non-selective product kills anything green and actively growing. 

How to Kill Weeds in Driveways and Patios
A person using weed killer in a wand applicator on a crack in a walkway.

While it may be tempting to simply pull weeds to sprout in driveway cracks or any other hard surface in your landscaping, that will not completely prevent them from growing back.


Apply combination pre- and post-emergent control products to these unwanted weeds. These herbicides quickly kill weeds growing in hardscapes and deposit chemicals that prevent new weed growth.

How to Kill Poison Ivy and Tough Brush
Weed killer being sprayed on a leaf of a noxious weed.

Noxious weeds like poison ivy, poison oak, kudzu and other tough brush love to invade landscapes. These tough weeds require a specialty weed control product to kill.


Use a post-emergent control specially designed to treat tough brush for fast elimination. These are typically non-selective control products, so be careful to avoid any plants that you want to keep alive. You can use a sprayer for more targeted application.

Organic Weed Killer

Organic weed killers exist for people who are concerned about the chemicals in traditional commercial weed killers. While these may cost slightly more than usual weed killers, they may be a worthwhile investment if you have indoor/outdoor pets, small children or anyone in the household with skin or breathing sensitivities.


Most natural and organic weed killers use formulas derived from citric acids or corn gluten. These raise the acidity of the soil surrounding the weeds which attacks the weed roots. Once to roots die, the formulas break down into the soil and dissipate.


Aside from cost, the other drawback of natural weed killers is that they often have to be applied several times to kill off the targeted weeds.

Consult your garden center to get the best advice on weed and grass killer and lawn insect and pest control. With professional advice and the right array of products you’ll learn how to kill weeds quickly and safely. With good advice from The Home Depot, you're sure to find the best weed killer for your needs, from the best crabgrass killer for your lawn to the right weed control for your veggie garden. Our guides are there to get you on your way to a lush lawn and weed-free landscape.