UK patios need cleaning once or twice a year to remove algae, moss, lichen, and ground-in dirt. Pressure washing at 1,500-2,000 PSI with a 25-degree fan nozzle suits most concrete and porcelain slabs. Natural stone requires lower pressure (under 1,200 PSI) or manual scrubbing with a pH-neutral cleaner. Biological cleaners cost around five to eight pounds per five litres and break down organic growth over seven to fourteen days without harming plants or drainage.
Key takeaways
- Clean your patio in spring or early autumn when algae growth is visible but temperatures are mild
- Pressure wash concrete and porcelain at 1,500-2,000 PSI with a 25-degree nozzle held 30cm from the surface
- Never pressure wash natural stone above 1,200 PSI or you risk etching and surface damage
- Biological cleaners break down algae and moss over 7-14 days and are safe for plants and drains
- Seal your patio after cleaning to slow algae regrowth and protect against staining for 3-5 years
- Remove weeds from joints before cleaning or they grow back within weeks
patio cleaning pressure washing patio maintenance algae removal moss removal
Our team produces practical UK gardening guidance from source research, contributor records and established horticultural practice. Editorial standards are overseen by Matt W.
