Weeds and Moss on Your Driveway: Prevention That Actually Works

Updated 15/09/2026 · 4 min read

Weeds and moss are the most common complaint about an otherwise sound driveway, and the fix depends heavily on which surface you have and how the driveway was originally built - a generic weedkiller isn't always the right answer.

Why weeds establish in driveway joints

Windblown seed and organic debris settle in any gap - block paving joints, cracks in tarmac, gaps between edging stones - and given enough moisture, they root there just as readily as in open soil. A driveway with joints that were never properly filled with jointing sand, or that has lost its sand over time, is far more prone to this than a well-maintained one.

Prevention on block paving

• Keep joints properly filled with kiln-dried sand - this is the single biggest factor, since a well-sanded joint gives weed seed nowhere to establish
• A polymeric jointing sand (which sets harder than standard sand) offers longer-lasting weed resistance than standard sand, at a modest extra cost
• Address weeds while they're small, before root systems develop enough to slightly lift surrounding blocks

Prevention on resin bound and tarmac

These surfaces are far less prone to weeds by design, since there are no joints for seed to settle in - weed growth here usually means a crack has developed, and addressing the crack promptly (see our resurfacing signs guide) both fixes the structural issue and removes the weed's foothold.

Why moss appears, and where

Moss favours damp, shaded areas - a driveway under tree cover, or a north-facing section that doesn't dry out quickly after rain, is far more prone than an open, sun-exposed area. Moss on a driveway is mostly a slip hazard and cosmetic issue rather than a structural one, unlike moss on a roof.

Dealing with existing growth

• A stiff broom and a proprietary path/patio cleaner handles most moss without needing pressure washing, which can dislodge jointing sand on block paving if used carelessly
• For weeds, treating at the root rather than just strimming the visible growth prevents rapid regrowth
• A weed-suppressing membrane laid beneath the sub-base during original construction is the most effective long-term prevention, but this needs to be included when the driveway is built, not added afterwards