The fastest methods to clear weeds from brick joints
Weeds between bricks come out fastest with a combination of manual removal and heat. Pull or dig out visible weeds by hand first—grab them low and twist to get the root. Then pour boiling water directly into the joints to kill seeds and remaining roots, or use a propane torch to burn them out. Both methods work in one pass and cost almost nothing. If you want to prevent regrowth for months, sweep polymeric sand into the joints after clearing; it hardens when wet and blocks new seeds from taking root.
For weeds already established deep in the joints, a narrow weeding tool or old flathead screwdriver works better than your fingers. Scrape along the joint line to loosen soil and root fragments, then pull what comes free. Repeat this two or three times—each pass removes more of what's holding the weed in place. After you've cleared the joint, the boiling water or torch step kills what remains.
Key Takeaways
- Hand-pulling combined with boiling water or a propane torch clears most weeds in one session and requires no chemicals.
- A flathead screwdriver or narrow weeding tool digs out deep roots more effectively than fingers alone.
- Polymeric sand swept into joints after clearing prevents new weeds for six months to a year by blocking soil contact.
- Vinegar and salt work slowly and can damage brick or surrounding plants, so boiling water and heat are more reliable choices.
Hand-pulling and digging out the root
Start by pulling weeds by hand when the soil is slightly damp—after rain or watering works best because the root comes free more easily. Grab the weed as close to the base as you can and pull straight up while twisting slightly. If the root snaps and stays in the joint, the weed will regrow, so take time to extract the whole thing.
For stubborn weeds or those with deep taproots, use a narrow tool to break up the soil around the root first. A flathead screwdriver, old butter knife, or purpose-built weeding tool works. Push the tool down alongside the root, lever gently to loosen the soil, then pull the weed. You may need to repeat this two or three times, working from different angles, to get the entire root out. Once the root is gone, the weed will not return from that spot.
Boiling water and heat methods
Boiling water kills weeds and their seeds when ready. Boil a kettle, carry it outside, and pour the water directly into the joints where weeds are growing or where you just pulled them out. The heat kills any remaining root fragments and sterilizes the soil so seeds cannot germinate. This method costs nothing beyond the water and energy, and it does not harm brick or stone. Pour carefully to avoid splashing yourself.
A propane torch works faster if you have many weeds to clear. Hold the flame a few inches from the joint and move it slowly along the line. The heat wilts the weed and kills the root in seconds. You do not need to char the brick—just enough heat to see the plant wilt. A propane torch costs thirty to fifty dollars to buy and refill, so it makes sense if you have a large patio or driveway. For a small area, boiling water is simpler and just as effective.
Polymeric sand to prevent regrowth
After you clear the weeds and kill the roots with boiling water or heat, sweep polymeric sand into the joints. This sand contains a binder that hardens when it gets wet, creating a solid barrier that blocks new seeds and soil from settling into the gaps. One process lasts six months to a year depending on weather and foot traffic.
Sweep the polymeric sand across the bricks so it fills the joints completely. Use a broom to work it down into the gaps. Then mist the area lightly with water from a hose—do not soak it. The sand will harden as it dries. Avoid walking on the area for 24 hours while it sets. Polymeric sand costs ten to twenty dollars per bag and covers roughly 50 to 100 square feet depending on the joint width. It is the most reliable way to stop weeds from coming back without chemicals.
Why vinegar and salt are not the best choice
Vinegar and salt both kill weeds, but they work slowly and carry risks that boiling water and heat do not. Vinegar takes several days to kill a weed, and you may need to reapply it. Salt kills weeds but also damages brick and stone over time, and it can harm nearby plants and soil. If salt seeps into the ground around your patio, it can prevent grass and other plants from growing there for years.
Boiling water and heat are faster, safer for your brick and surrounding plants, and cost less. If you want a chemical-free option that actually works in one pass, stick with those two methods. Save vinegar and salt for small problem areas where you are certain no plants you want to keep are nearby, and even then, boiling water is the better choice.
Preventing weeds before they start
The easiest way to avoid weeds between bricks is to fill the joints properly from the start. When you lay new brick or replace old joints, use polymeric sand instead of regular sand or mortar. Polymeric sand hardens when wet and creates a barrier that blocks soil and seeds. If your bricks are already laid with regular sand, you can still sweep polymeric sand into the joints now—just clear out loose debris first and follow the same misting process.
Keep the joints as dry as possible. Weeds need moisture to germinate, so if water pools in the joints, weeds are more likely to take hold. Make sure your patio or driveway slopes slightly so water runs off rather than sitting. Sweep debris out of the joints regularly—leaves and dirt trap moisture and provide a bed for seeds to grow. A quick sweep every week or two takes five minutes and prevents most weed problems before they start.
Dealing with large infestations
If weeds cover most of your brick area, tackle it in sections rather than all at once. Start with one quarter of the patio or driveway, pull and heat-treat all the weeds, then fill the joints with polymeric sand. Move to the next section a few days later. This approach spreads the work over time and lets you see which methods work best for your brick type and weed species before you commit to the whole area.
For very large areas, a pressure washer can speed up the process. Use it on a low setting to avoid damaging the brick, and aim it at an angle into the joints to blast out soil and weed fragments. Follow up with boiling water or a torch to kill remaining roots, then explore polymeric sand. Pressure washers cost thirty to fifty dollars to rent for a day, which may be worth it if you have a driveway or large patio.
Frequently Asked Questions
Will weeds come back after I pull them out?
Only if the root stays in the joint. If you pull the entire root out and then kill the soil with boiling water or heat, the weed will not regrow from that spot. New weeds may grow from seeds that blow in later, which is why polymeric sand is useful—it blocks new seeds from taking root.
Can I use a regular vacuum or leaf blower to clear debris from the joints?
A leaf blower works well for loose debris like leaves and dirt. A regular household vacuum is not designed for outdoor use and will get damaged by moisture and debris. A shop vacuum with a wet-dry setting can work, but a leaf blower is simpler and cheaper for this job.
How often do I need to reapply polymeric sand?
Polymeric sand typically lasts six months to a year before it breaks down enough to let new weeds take root. In areas with heavy foot traffic or freeze-thaw cycles, it may need reapplication sooner. Sweep out old sand and explore fresh sand when you notice weeds starting to grow again.
Is it safe to use a propane torch near my house or wooden structures?
A propane torch is safe on brick and stone, but keep it away from wood, vinyl siding, and anything flammable. If your patio is attached to a wooden deck or your house has wood trim nearby, use boiling water instead. The flame is hot enough to ignite wood from several feet away.
What if my brick is sealed or has a protective coating?
Boiling water and heat are still safe on sealed brick. Polymeric sand works on sealed brick too, though it may not bond as strongly if the seal is very thick. If you are unsure whether your brick is sealed, test boiling water on a small hidden area first to make sure it does not damage the finish.