How to Clean Moss & Algae Off a Wooden Deck

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Things You'll Need

  • Bucket

  • Chlorine bleach

  • Long-handled scrub brush


Cover or move any plants or items that can't be exposed to bleach before cleaning.

Prevent future moss or algae growth by improving water drainage or increasing sun exposure to the deck.

Sweep the deck often to prevent moss from taking hold.

Moss and algae can grow on almost any surface in wet or shady conditions. Moss appears in flat or fluffy green tufts. Algae appear as a green, slimy film. When wet, algae and moss can create slippery and hazardous conditions on walkways. If your wooden deck has moss or algae growth, you can remove it with an inexpensive, homemade deck cleaner that will effectively kill moss and algae. Clean your wooden deck at least once a year to help prevent moss and algae growth.


Step 1

Fill a bucket with 1 gallon of warm water and add 3/4 cup of chlorine bleach.

Step 2

Pour the bleach solution onto the wooden deck. Allow the solution to sit for at least 10 minutes.

Step 3

Scrub the deck thoroughly with a scrub brush to remove all of the moss and algae.

Step 4

Rinse the wooden deck with a garden hose to remove any bleach residue and allow the deck to air dry.



Shelley Marie

Shelley Marie has been writing professionally since 2008 for online marketing and informational websites. Her areas of expertise include home, garden and health. She holds a Bachelor of Science in business administration and an associate degree in medical billing and insurance coding, both from Herzing University.