Lichen on stone walls, caps and steps
Lichen is not dirt sitting on stone, it is an organism anchored into the surface. That is why it survives rain, brushing and most of what people try before calling someone.
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Monday to Saturday, 8am – 7pm
- Never scrape lichen off soft stone
- Expect gradual weathering off, not instant removal
- Copings and steps hold it worst
Why it holds on so well
Lichen roots into micro-fissures in the stone face, which is what gives it the grip that algae lacks. Pulling or scraping it off takes fragments of the stone with it, and on softer stone that leaves visible pitting.
Where it shows up first
Wall copings, gate piers, steps and any horizontal surface that stays damp are where it establishes, because those hold water longest. South-facing stone is not immune, though it usually carries less.
What treatment achieves
A treatment kills the organism and it then weathers off over following weeks rather than coming away instantly on the day. Owners expecting an immediate result are sometimes surprised, so it is worth knowing that up front.
Common questions
- How long until it looks clear?
- Weeks rather than hours, depending on rain and exposure. The kill happens on the day, the shedding takes time.
- Will it come back?
- Eventually, on the same damp surfaces. Intervals are measured in years on stone.
- Can granite be pressure washed?
- It tolerates more than most stone, but pressure alone does not deal with lichen, so it is the wrong tool for this job.
Similar situations
Send close-up photos of the affected stonework and we will price a treatment that suits the material.
Get a written quote