Why Are Weeds Growing Between My Pavers (And How Do I Stop Them)?

You spent a bunch of money on a nice new patio with pavers, and you’ve already got weeds coming up in between the stones. When you pull them out, they just come right back a few weeks later. The weeds are annoying, and they shouldn’t be causing such a problem. When they are, it’s possible the patio wasn’t built correctly.

My name is Randy Thompson, and I started All-Out Hardscapes LLC. We’re a veteran-owned, certified Techo-Pro installer, and for more than 10 years we have built over 150 patios, walkways, and outdoor living spaces all over Savannah and the Coastal Lowcountry, from Wilmington Island to Savannah Quarters. Weeds are one of the most common things people look for, but it’s rare that I get complaints about weeds from my customers. There’s a reason for that, and it’s reassuring to a homeowner to know why.

The truth is that weeds in a patio almost always come down to one thing, and once you see it, you’ll know exactly why it’s happening and what you can do to stop it. Let me explain where the weeds really come from, why pulling them feels like a losing battle, and how a patio can be built so weeds aren’t able to start in the first place.

Why Are Weeds Growing Between My Pavers?

Well, weeds have to have dirt in order to grow, and there are always seeds landing on top of your patio. They’re not coming up from beneath it. Pollen, grass seed, and tiny bits of organic matter ride in on the wind and the rain and end up in the gaps between your pavers. Leaves and grass clippings break down after a while and leave behind a thin film of soil. All a seed needs is that little bit of dirt to sit in, some sun, and some water, and it will sprout.

So weeds are not really a sign that nature is winning. It just means that there’s something in the joints for them to root in. So the real question is not how to kill the weeds you have right now. It’s what is sitting down in those joints feeding them, and that comes straight back to how the patio was built.

Why Does Pulling Them Never Seem to Work?

Because that’s just treating the symptom, not the cause. Most of the patios built in our area are installed on sand. The crew digs out the yard, lays down a few inches of crush-and-run, which is a mix of crushed stone and stone dust that packs down hard, and then beds the pavers in two to three inches of concrete sand. The joints get filled with regular sand too.

That sand is the problem. Sand holds moisture, and it catches and holds the dirt and seeds that work their way in. So every weed you pull leaves the root bed sitting in the same place, ready for the next seed. You’re actually not fighting the weeds themselves. You’re fighting the sand that allows them to grow, which is why it feels like you’re losing the battle.

How Do I Actually Stop Weeds in a Paver Patio?

You stop them by taking away the two things they need to grow: dirt and an open joint to root through. This is something you do during the construction part, and it’s the biggest thing that separates a patio you can forget about from one you are battling with every year.

Everything is dependent on the base, and it has to be the right kind of base. We don’t use sand. We build on an open-graded base, which just means clean gravel with all the dirt and dust washed out of it so water runs straight through it. We use four inches of clean number 57 stone, which is roughly three-quarter-inch gravel, for the foundation, and a two-inch bedding layer of clean number 789 stone, a smaller pea-sized gravel, directly under the pavers. There’s no sand or soil at all. And clean gravel leaves weeds no dirt to be able to grow in, which is exactly why a good base means you won’t have this issue. Building it this way alone shuts down almost the entire weed problem before the patio is even finished.

Keeping that gravel clean is no easy task either. When we dig a patio out, what comes up is dirt, and dirt is exactly the problem. So we’re very careful not to let any of it mix into our stone. The gravel arrives clean, and we keep it clean and free of dust and debris until the pavers are set on it. No dirt in the system means we’ve taken away the one thing a weed has to have in order to grow.

Then there are the joints between the pavers, and this is the part most people get wrong. We fill those joints with polymeric sand, which is a fine sand that binds together like grout. People hear the word sand and they picture that loose stuff in a sandbox. That’s not what polymeric sand is. Once it’s in the joint, it behaves just like grout. When we sweep it in dry, a little of it sifts down toward the gravel. But as soon as it gets wet, it clumps, bonds to itself, and grabs the sides of every paver all at once, the same way grout grips the edges of tile. With a Techo-Bloc paver like the Blue 60, the whole face of the stone actually pulls water down through it, so even a thin trail of sand that works into the gravel doesn’t wash away. It bonds right where it lands. And once it cures, it stops sticking and stays locked in place. A sealed joint doesn’t allow a place for a weed seed to settle and almost nothing to root into. That’s the main reason we don’t really get complaints about weeds on the patios we build.

What If My Patio Already Has Weeds?

If you’re reading this and you already have a patio that’s sprouting weeds, don’t worry: you’re not stuck, and you probably don’t need to tear it out. Pull or spot-treat the weeds that are there, then blow the surface clear of leaves and dirt so new seeds land on bare stone instead of into dirt. If the joints look low or washed out, re-sand them. Polymeric sand won’t last forever, but there’s no real time frame on how long it will last either. Under a big oak tree where you’re pressure washing all the time, you might have to re-do it every six months. In an open backyard with a darker paver that hides dirt, three to five years is realistic, and I’ve looked at patios that were older than six years that still didn’t need it.

Just know that on a patio that was set on sand, that routine will cut the problem down, but it won’t stop it, because the sand bed underneath keeps holding moisture and dirt. We build new patios and outdoor living spaces, we don’t do weed-removal. But understanding why it keeps happening tells you what to look for, whether you’re keeping up the patio you have or planning the one you want next.

When a Few Weeds Are Not a Red Flag

If you’ve only got a weed or two here and there, it doesn’t mean your patio was built wrong. Anything with seams will collect dirt after a while, and if leaves and clippings are left to sit on any surface long enough, weeds will try to grow in that thin layer on top. That’s just simple maintenance, not a base failure, and a quick sweep or a rinse takes care of it.

What tells you the build is the real problem is weeds coming up thick, fast, and in the same spots right after you have cleared them. That’s how you’ll know if there’s dirt down in the joints and a sand bed underneath feeding them. One is a basic Saturday-morning chore. The other is a good reason to think hard about how your next patio gets built.