Remove biological growth safely and keep it from coming back. In this child category we separate mold vs mildew vs algae, map each to the right chemistry (sodium hypochlorite vs oxygen bleach), and set prevention plans—so decks, siding, and fences stay clean, non-slip, and cheaper to maintain over 10 years.
Mildew → thin gray/brown film that wipes off easily; thrives on shaded, damp wood.
Black mold → spotty to patchy black colonies; needs safety-first handling and correct dwell times.
Green algae → slick, bright/dark green layer; common on north-facing fences and constantly damp zones.
Read next: Black Mold on Deck • Best Deck Mildew Remover • Green Algae on Wood Fence: Removal & Prevention
Sodium hypochlorite (bleach) for fast mold/mildew knock-down; protect plants/metals, control dwell, then rinse thoroughly and normalize pH per product guidance.
Oxygen bleach (sodium percarbonate) for fiber-friendlier cleaning and maintenance washes; longer dwell, light agitation, good for periodic upkeep.
Never mix bleach with acids/ammonia; always test in a small area first.
Read next: Best Deck Mildew Remover • Safety & dwell specifics: Black Mold on Deck
Pre-wet adjacent vegetation, tarp delicate plantings, and keep spray in a controlled fan with the grain. Favor soft-wash methods over aggressive pressure to avoid raising grain or driving water into joints. Final-rinse thoroughly and allow full dry-back before finishing.
Read next: Workflow hub: Wood Restoration • If discoloration remains: Remove Stains from Wood Siding & Decks
Fix moisture and shade drivers first: redirect sprinklers, clear leaf litter, improve drainage/airflow, and trim vegetation. Choose finishes with good pigment load and built-in mildewcides; set light maintenance cleans before growth re-establishes.
Read next: Algae control on fences: Green Algae on Wood Fence • Ongoing cleaning choice: Best Deck Mildew Remover
Persistent regrowth around posts, ledgers, or bottom boards can signal trapped water and early decay. Diagnose and repair structure before finishing.
Read next: Soft Rot in Deck Posts • Consolidate/patch logic: Wood Rot Consolidants
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Green Algae on Wood Fence Short version: Green algae on wooden fences is normal, fixable, and (with the right routine) manageable long term. Below you’ll find safe, step-by-step methods, product ratios, pro tips, and a seasonal plan to keep your fence clean without killing nearby plants. Understanding Green Algae on Wooden Fences What Is Green […]
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Deck Mildew Remover: Bleach vs Oxygen Cleaners If you’re hunting for the best deck mildew remover, the internet will tell you “bleach is faster.” That’s only half the story. After restoring 1,000+ decks since the late ’90s, I’ve run enough side-by-side tests to separate myths from what actually saves your deck (and your plants). Below
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Black Mold on Deck: Safe Removal & Prevention Methods Safety First: Black mold and heavy mildew release spores when you scrub. Wear proper PPE (respirator, gloves, eye protection), keep kids and pets away, and avoid mixing chemicals. If the affected area is larger than 10 sq ft or anyone at home has asthma or is
