Fall Pressure Washing in South Carolina — The Reset Wash

Spring gets most of the attention, but fall pressure washing in SC is often the more important clean. Five months of 85-95°F temperatures and 70-80% humidity have given algae, mildew, and black mold ideal conditions to establish on every surface. Driveways show green staining. North-facing siding has dark streaks. Decks have a slick film. If you leave that biological growth to sit through winter, it bonds deeper into the surface and becomes harder to remove in spring.

Decks and patios are the top priority because they go largely unused after October and don't get natural rinse from foot traffic. Algae and mold that over-winter on wood decking penetrate deeper with each freeze-thaw cycle. Driveways with green or black staining benefit from a fall clean to stop the growth before it spreads into cracks. House siding, particularly north-facing walls, holds mildew year-round and is best addressed before cold temperatures reduce the effectiveness of cleaning solutions.

Tannin stains from oak leaves are a Midlands-specific problem. Wet leaves sitting on concrete for weeks deposit tannin that etches into the surface — particularly on newer concrete and composite decking. Cleaning your surfaces in October removes tannin before the oak leaves start their December drop, and a second light rinse in January clears the final wave. Left over winter, tannin stains require acid washing or grinding to remove fully.

Pressure washing is most effective above 50°F, when cleaning solutions stay active and surfaces dry properly. In the Midlands, October is ideal — temperatures are consistently in the 60s and 70s, humidity has dropped from summer peaks, and sun angles are still high enough for surfaces to dry same-day. November is still workable through mid-month. Once December cold snaps arrive regularly, schedule the following spring instead to ensure cleaning solutions activate properly.