Algae on a Deck

Algae on your deck is not just unsightly, it can be dangerous. Spots with even a light coating of algae can become as slippery as ice when wet, or even first thing in the morning when your deck is covered with dew. Algae typically appears on decks after the winter, or following periods of humid or rainy weather. Algae is easily spotted on most decks, wherever a light green color appears. If left untreated, it can permanently stain the wood. When you see algae spots appear, treat and remove them quickly to avoid stains and accidents.

Things You'll Need

• Garden hose
• Bleach or oxygen bleach
• Stiff scrub brush with pole or broom

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Instructions

1. • 1

     Remove all furniture, plants and anything unattached from the deck.

   • 2

     Rinse the deck with water from a garden hose to remove dust and dirt, and open the pores of the wood to allow deeper cleaning.

   • 3

     Mix 1/2 cup of bleach with 1 gallon of hot water. Make the solution stronger, up to 1 cup bleach to 1 gallon water, for more serious algae problems not addressed right away.

   • 4

     Use a stiff brush on a pole or broom to generously apply the solution to the deck. Allow the cleaner to set for up to 30 minutes.

   • 5

     Rinse thoroughly with a garden hose. Repeat the treatment, if needed.