Brown Tannin Stains on Pavers and Concrete
Under a live oak, the brown staining spreading across your driveway is not dirt washing down. It is tannin leaching out of leaf litter into the surface, and it needs different treatment from everything else on the drive.
What tannin staining is
Oak leaves, acorns and bark contain tannic acid. When they sit wet on a porous surface — and in Central Florida they sit wet for most of the year — the tannin leaches out and soaks into the paver or concrete beneath.
The result is a brown to reddish-brown discoloration, often in the exact shape of the debris that caused it, spreading and merging over a season into general staining.
Because it soaks in rather than sitting on top, it behaves much more like rust than like dirt.
Why this is a Winter Park and Orlando problem specifically
The live-oak canopy that defines the older neighbourhoods here is the single biggest producer of tannin staining in Central Florida. Winter Park's brick streets and paver drives sit directly under it.
Maitland, College Park, Longwood's Sweetwater Oaks and much of Casselberry have the same issue for the same reason — mature canopy directly over hardscape, with leaf litter that is never fully absent.
It builds continuously and it is far easier to stay ahead of than to reverse, which is why homes under heavy canopy benefit from a shorter cleaning interval than the rest of the region.
What not to do
Do not just pressure wash it. Pressure removes the surface layer and takes the top of the stain with it, so the drive looks improved and then darkens again within weeks as the remaining tannin wicks back up.
Do not use bleach. It lightens the surrounding surface more than the stain, leaving the stain more obvious by contrast.
Do not leave leaf litter sitting through the wet season. The staining is proportional to how long debris stays wet on the surface.
How we remove it
Tannin needs a cleaner formulated to break it down chemically, with dwell time, before any mechanical cleaning. Applied first, it lifts the stain out of the pore structure rather than shaving the top off it.
The surface is then cleaned with a surface cleaner for even coverage, and on pavers we check the joint sand — tannin removal involves enough rinsing that thin joints will need topping up.
Most tannin staining comes out well. Very old staining on unsealed, highly porous pavers can lighten rather than fully clear, and sealing afterwards is worth considering to stop it soaking in again.
Questions we get about this
Why does my driveway go brown again so soon after cleaning?
Will sealing stop it coming back?
Do I need to cut back my oak?
Can every tannin stain be removed?
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