How to Stop Weeds and Ants Between Pavers

Quick answer

• Remove debris so joints stop behaving like soil.
• Clean the surface without blasting joint sand out.
• Let joints dry fully before adding new sand.
• Re-sand and compact (this is where most DIY jobs fail).
• For longer-lasting joints, polymeric sand must be installed exactly per the technical data sheet.^[1]

Why weeds and ants keep coming back

Weeds usually start in a thin layer of organic material that settles into joints: leaves, mulch dust, lawn clippings, and windblown dirt. Ants prefer loose sand and small voids. When joint sand washes out, ants can expand the gaps, and the cycle accelerates.

Step 1 Diagnose what you have

• Joints look low or empty: you need a joint sand refresh (see pavers joint sand).
• Ant hills or fine sand “volcanoes”: joints are loose and ant-friendly.
• Weeds everywhere but pavers feel stable: debris is turning joints into soil.
• Pavers rock or sink: base/drainage may be involved; re-sanding alone is temporary.

Step 2 Clean joints without washing them out

The biggest mistake is aiming high pressure straight into joints. That removes joint sand fast and invites weeds and ants back. Sweep first, clean the surface with controlled pressure and angle, rinse, then let the joints dry.

If you’re choosing between methods for exterior cleaning, this overview explains why softer approaches can be safer on certain surfaces: soft washing benefits.

Pro tip: pair pavers with nearby surfaces like patio power washing or driveway power washing for a consistent exterior.

Step 3 Regular sand vs polymeric sand

Regular joint sand is simple and easy to top up. Polymeric sand can help resist washout and reduce weed growth and insect penetration when installed correctly, but it is sensitive to moisture, activation, and curing time.^[1]

Step 4 The correct re-sanding process

1. Clear weeds and loose joint material.
2. Clean the surface without blasting joints.
3. Dry joints completely (critical for polymeric sand).^[1]
4. Sweep sand into joints in multiple passes.
5. Compact, top off, and compact again.
6. For polymeric sand, activate exactly as instructed and protect the cure window.^[1]

Most common mistakes

• Blasting joints with pressure and removing sand.
• Re-sanding damp joints (polymeric sand needs dry conditions).^[1]
• Skipping compaction so sand stays shallow.
• Using chemicals casually instead of following the label. In the U.S., the label is the law.^[2]

Chicago-area freeze-thaw and spring rain can speed up washout, so check joints in early spring.

For seasonal timing: summer power washing guide.

When to call a pro

• Large areas with low or empty joints.
• Constant ant activity across multiple zones.
• Weeds return fast after each cleaning.
• Any rocking, sinking, or pooling water.

FAQ

Will polymeric sand stop weeds forever

No. It can reduce growth, but sweeping and seasonal cleaning still matter because weeds often start in surface debris.

Will polymeric sand stop ants completely

Not completely, but stable joints remove the loose sand and gaps ants prefer, which can reduce repeat activity.

Can I pressure wash pavers after re sanding

Yes, but avoid aiming into joints. Respect the product curing guidance before aggressive cleaning.^[1]

What weather window do I need for polymeric sand

Dry joints and a rain-free window are typical requirements. Always follow the technical data sheet for your product.^[1]

Is it safe to use weed killers or insect products between pavers

Use only products intended for that use and follow the label. The pesticide label is a legal document in the U.S.^[2]

Should I seal my pavers after re sanding

Sometimes. Sealing can help reduce staining and slow debris embedding, but timing depends on the surface and curing period.