What Kills Grass and Weeds Permanently? [Busting 5 Popular Weed Control Myths]

To remove weeds and unwanted grasses permanently it is essential to destroy them down to the roots. Otherwise, the same weeds will regrow. A plant that appears withered or brown aboveground may still have living roots. Use weed killing methods that kill weeds and grass roots to truly eliminate them.

Best Tactics

• Systemic herbicides
• Digging/hoeing
• Hand weeding
• Covering weeds to block air and sunlight
• Solarization

Avoid These Methods

• Vinegar
• Salt
• Bleach
• Baking soda
• Boiling water

Many common “homemade” solutions won’t kill weed roots. All they will do is briefly slow down weeds. If you use ineffective methods, it will only be a matter of weeks before invasive grasses and weeds take over your lawn and garden once more.

5 Best Methods to Kill Weeds and Grass Permanently

Weeds can be killed permanently by using chemicals or through all-natural means. The key is to use methods that destroy weeds down to the root without poisoning the ground or harming desirable grass, trees, and other plants. To reclaim an area overrun by weeds, stop weeds in pavers and pebbles, or clear out a flower bed, use these methods.

Permanent Weed and Grass Killer Spray

A non-selective weed killer, such as Roundup, is a great option for killing weeds and grass permanently. The Glyphosate in Roundup works by infiltrating the plant through the leaves. From there, it attacks all plant systems and kills them completely, including the roots.

• If you plan to plant desirable grass or garden plants after clearing out weeds, use this weed killer spray.
• To kill all vegetation and prevent it from growing back for up to 12 months, apply this herbicide.

Unlike salt, Roundup applied to an area is extremely unlikely to damage plants via water runoff. As long as nearby plants aren’t sprayed with the herbicide, they will remain unharmed.

Digging or Hoeing Weeds and Grass

If you want to get rid of unwanted weeds and grass for good, take them out by the roots. When getting rid of weeds in large areas, such as overgrown yards or garden beds, a shovel or hoe can be used to destroy weeds and their roots.

• Use a shovel or hoe to dig down and remove weeds, roots, and all.
• Discard weeds once they’ve been dug out, to prevent them from re-rooting or dropping seeds.

Destroying weeds in this manner is an all-natural, organic solution and is far more effective than vinegar or bleach. All you need is a spade, some work gloves, and a little time to get the job done.

Hand Weeding

In some areas, using a hoe to quickly dig up weeds isn’t an option. This is where hand weeding comes in. This is the perfect chemical-free solution for getting rid of grass growing through concrete, as well as weeds sprouting among flowers.

• Use this hand weeder to easily remove weeds along with their roots.
• Discard weeds. Don’t add them to compost. Some weed seeds can survive the composting process and may sprout once the compost is spread.

It may not be glamorous, but hand-weeding is an organic weed solution that works. It’s a tried-and-true standby for good reason.

“Starve” the Weeds

Like all plants, weeds need air and sunlight for continued life. A simple method to kill weeds is to simply deprive them of these essentials. To do so:

• Cover large areas overrun by weeds and unwanted grass with black plastic, newspaper, cardboard, or plywood.
• In 2–3 months, all plants under the covering will be dead. Covering material can then be removed.

While this won’t work for isolated weeds growing among desirable plants and grass, it’s a great way to reclaim large weedy areas. Simply cover the weeds and forget about them for a few months. Nature will do the work for you.

Soil Solarization

Soil solarization uses the sun’s heat to raise soil temperature in a large area. This “cooks” weeds to kill them. It also works to kill weed seeds in the soil, which will help keep an area weed-free permanently. To solarize soil:

• Perform soil solarization during peak summer heat (temperatures above 80℉/25℃)
• Soak the weed-infested area with 1 inch of water (about 1 hour with the sprinkler).
• Lay clear plastic over the entire area.
• Bury the edges of the plastic to keep it in place. Weigh down the plastic with stones and make sure air cannot flow in and out.
• Leave the plastic in place for 4 weeks.

This solution works more quickly for killing weeds in large areas than depriving plants of air and sun. This is because solar heat is trapped between the plastic and the ground, which superheats the soil, destroying weed roots and dormant weed seeds.

The Truth Behind 5 Weed Control Myths

While there are highly effective, natural ways to get rid of weeds permanently, some proposed solutions aren’t true weed killers. Several commonly suggested homemade weed killers are ineffective or potentially harmful to your yard. Here’s the truth about these homebrew weed sprays.

Does Vinegar Kill Weeds Permanently?

False: Vinegar only kills aboveground weed growth.

Weeds and grass will grow back after an application of vinegar. This is because the acetic acid in vinegar burns plant leaves and stalks on contact, but vinegar is completely neutralized by soil. In other words, vinegar won’t penetrate the roots of weeds.

• Vinegar will not kill weed and grass roots.
• Most species of weeds and invasive grass will regrow quickly following vinegar application.

If you spray weeds and unwanted grasses with a vinegar and dish soap solution, the tops of the plant will turn brown and wilt. However, in a few weeks the weed will sprout back from the unharmed root. Vinegar is not a permanent weed solution.

Does Salt Permanently Kill Weeds and Grass?

True: But it can wreak havoc on your lawn and garden

Salt is a dangerous additive. Think twice before you fill a spray bottle with homemade weed killer made from vinegar, Epsom salt and Dawn dish soap. If applied carelessly, you can wipe out whole portions of your lawn and garden.

• Salt poisons soil, killing all plants and preventing future plant growth for months or years.
• Salt is easily carried to other portions of your yard by water runoff.
• If you apply salt to one area, salt carried by water runoff can kill large portions of your lawn or decimate your vegetable garden.

All varieties of salt (rock, Epsom, sea, and table salts) are essentially soil poison. By spreading them on weeds and grasses, you make the soil inhospitable to plants for a very long time. This may sound great, since you want to kill weeds and grass permanently, but there’s a catch. Salt is very easily carried by water. Even if you apply salt to a small area, future watering and rainfall can spread salt into other areas of the yard, leaving huge patches of dead grass or garden plants.

Will Bleach Kill Grass and Weeds Permanently?

False: Bleach will not kill weed roots.

Much like vinegar, bleach works by drying out the portions of a weed or grass it is directly exposed to. Whatever portion of the plant bleach doesn’t touch won’t be harmed. Hardy weeds, such as dandelions and nutsedge will only be momentarily damaged by bleach.

• Bleach only kills aboveground portions of the plant—roots remain ineffective.
• Perennial weeds, and many annuals, will regrow shortly after bleach application.

Bleach is not a good weed killer substitute. It is a temporary weed control measure at best. Do not reach for extra-strength outdoor bleach to try to attack weeds with more firepower. Much like extra-strong vinegar (horticultural vinegar), concentrated bleach can be dangerous to handle or inhale. Additionally, it is not a more effective weed killer.

Is Baking Soda an Effective Weed Killer?

False: Baking soda does not completely kill weeds.

Much like vinegar and bleach, baking soda works by drying out plant leaves and blades. Even a solution of baking soda mixed in water won’t penetrate well enough to damage weed and grass roots. Remember, some weeds can send roots 6 inches (15 cm) or deeper.

• Baking soda has the same limitations as bleach and vinegar—it won’t kill weed roots.
• Rather than a weed killer, use baking soda as a grass protector. Pour baking soda solution on pet urine spots in your yard. This will prevent animals from urinating in the same spot and actually preserve grass and plants.

Don’t go in for methods that recommend mixing several ingredients (white vinegar, salt, baking soda, etc.) These compounds have the same limitations and risks as the individual components do on their own.

Is Boiling Water Good for Killing Weeds?

False: Boiling water will not kill weed roots.

If you want to get rid of weeds for good, boiling water is not an effective solution. While leaves and stalks of grass and other unwanted plants will be damaged by boiling water, the weed roots will be insulated by the soil. Only newly sprouted weeds that haven’t developed mature roots will be killed.

• Boiling water will mostly kill shallow-rooted weed seedlings.
• Mature weeds will only be temporarily damaged by boiling water.

To get rid of weeds and keep them out, you’ll need to take stronger measures for weed control. Boiling water won’t do the trick when battling established weeds and grasses.

What Kills Vegetation Permanently?

If you are looking to kill weeds and pest grass permanently, avoid using vinegar, bleach, baking soda, and salt solutions. Most of these homemade solutions are not effective at killing weeds because they do not kill established weed roots. A mature weed treated with vinegar or bleach will regrow soon after treatment.

If you want to use a natural weed killing process that works, hand dig weeds, block them from sunlight with dark plastic, or solarize them with clear plastic. For an effective weed killer spray that kills weed roots, choose a non-selective herbicide such as Roundup. This will eliminate weeds quickly and completely.