The short answer: more often than you think. Miami-Dade and Broward County average over 60 inches of rain per year, with heat and humidity that never fully let up — even in "winter." Algae, mold, and mildew don't take a season off here.
By Surface Type
Driveways & Walkways: Every 6–12 months. Shaded driveways and anything near a tree line can go green in 4–5 months.
Roofs: Every 1–2 years with soft wash. Dark streaks on a tile or shingle roof aren't dirt — it's a living organism called Gloeocapsa magma, and it spreads.
House Exterior: Once a year is a solid baseline. If you're near the ocean, twice a year is better — salt air accelerates buildup.
Pool Decks & Patios: Every 6–12 months. These get foot traffic, pool water, and shade — a perfect combination for algae growth.
If your HOA has a maintenance schedule, build your cleaning around it. Most Miami-Dade HOAs expect visible cleanliness year-round.