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how do weeds grow in concrete

Weeds leave your driveway and sidewalks looking a little ragged. Luckily, removing them can be simpler than you’d think.

Once you’ve gotten rid of the weeds in the first place, you want to prevent them form coming back. There are a couple easy things you can put between slabs to keep your driveway or patio permanently plant-free.

Keeping your home looking well-groomed means getting rid of these problem plants. Luckily, there are strategies to help you remove weeds between slabs, as well as methods to keep them from growing back.

Finally, if nothing else has worked, you can use heavy-duty weed removers. There are several weed removers that linger for months or years where they’re sprayed. “Extended release” or “year-long” guarantees are a good clue that you have something that will stick around.

Use Commercial Herbicides – Carefully

Weeding after a heavy rain is the most efficient strategy. Soil is softest after a heavy rain, so plants are vulnerable to being pulled up, roots and all. After the next drenching rain, you’ll be able to clear out your weed problem for good.

Pouring vinegar on weeds in your driveway or sidewalks will remove them over a week or two. You may have to apply the vinegar several times, though, depending on the weather. Rain can wash it away before it takes effect.

Weeding between concrete slabs or bricks can be a pain, because the root of the plant is safely nestled where you can’t reach it. That doesn’t mean the situation is hopeless, though. You have plenty of options to help make your driveway or patio weed-free.

Does Boiling Water Remove Weeds?

You can get concrete or asphalt crack sealant at most hardware stores. Sealing cracks takes an hour or two, depending on how many you want to seal, and then a day for the seals to dry. Once you have your cracks sealed up, you have that much less space for weeds to invade.

If you have many weeds, or if you have garden tools on hand, using a V-notch weeder can make things easier. These tools use a special notched design to pull weeds more effectively.

How do weeds grow in concrete

Concrete might be the perfect building material — tough, fireproof, a good insulator and long-lasting. The Roman Coliseum and Pantheon, both built around 2,000 years ago, still draw tourists who marvel at how well these concrete buildings have survived. And yet even concrete can succumb to aggressive weeds.

Concrete Basics

The terms “concrete” and “cement” are often incorrectly used to refer to the same material. However, cement is actually an ingredient of concrete. Cement is a fine powder, typically composed of ground clay and limestone, that when mixed with water creates a strong paste. The paste binds a mixture of sand and gravel or crushed rock, and the resulting material is concrete — hard, solid, dependable, capable of lasting for millennia.

Weeds Can Contribute to Concrete Decay

Like anything exposed to the elements, concrete is subject to environment stresses. Extreme cold and heat cause expansion and contraction, gradually weakening the material. Earthquakes and more subtle ground movements introduce cracks and breaks into concrete structures. Acid rain can create cracks and holes. Once a crack or break has appeared in concrete, weeds are close behind. They flourish in poor soil and grow quickly, pushing against the weakened concrete and causing more breaks and cracks — which makes room for more weeds. If left unchecked, a flourishing weed population can break apart sidewalks, driveways, roads and buildings.

How do weeds grow in concrete

Weeds seem to grow virtually anywhere, even poking leaves out of cracks in concrete expansion joints on driveways and sidewalks. While newly laid concrete doesn’t have such problems, settling produces cracks after several years, allowing weed seeds to gain a foothold. Although hand pulling will temporarily remove this unwanted greenery, sections of roots often remain, allowing weeds to regrow.

Chemical, Organic Controls

To avoid regrowth after pulling weeds, spray commercially available weed killer into the cracks. If you are concerned about the effect of chemicals on the environment, however, a number of organic options can kill weeds. Applying table salt to the cracks will make the soil underneath chemically unbalanced, causing weeds to wither and die. Pouring boiling water on the weeds and in the cracks might also be effective. Another solution is a mixture of 1 cup table salt dissolved into1 gallon household vinegar and 1 tablespoon dishwashing detergent. Spray on the weeds and repeat as necessary.

Sealing the Cracks

Filling the cracks is another, possibly more effective alternative. For an organic solution, try shredded bark or pebbles. Polymeric joint sand, a mixture of regular sand and resin, solidifies to a mortar, blocking air, water and light from reaching weed seeds and roots.