Garden guide
How to Clean a Patio (and Keep It Clean Longer)
The short version
Sweep, scrub with soapy water for a light clean, or pressure wash carefully for a deep one — then re-sand the joints and consider a sealant. The aftercare is what separates a patio that stays clean from one that's green again by autumn.
Pressure washing without the damage
Use a fan nozzle, keep the lance 30cm from the surface at a shallow angle, and work along the joints rather than blasting into them. Full-power jets strip the face off slabs and excavate pointing — the two most expensive mistakes in patio care. Test a corner first, especially on softer sandstone.
Black spot and algae
Black spot is a stubborn lichen that washing alone won't shift — use a dedicated patio black-spot remover, leave it to work, then rinse. Green algae usually lifts with the wash itself. Keep bleach-based cleaners well away from lawns and borders, and rinse run-off away from drains.
Re-sand the joints afterwards
Every wash takes some jointing with it. Once the paving is bone dry, brush kiln-dried sand into block-paving joints, or top up mortar and compound joints on slabs. Our sand calculator works out kiln-dried quantities from your patio area.
Keeping it clean
A breathable patio sealant after a deep clean slows algae and black spot for a couple of years. Beyond that: sweep little and often, trim back overhanging shade where you can, and give it one proper clean each spring rather than a battle every few years.