How To Remove Green Algae From Wooden Deck
By Jane Malham
If you’ve put a lot of work into building and maintaining a wooden deck, spotting green algae or mold growing on it can be incredibly frustrating. This algae growth makes your deck look filthy and leaves a slippery film, making your deck a hazardous place to walk.
Don’t wait until someone takes a tumble before you take action. See how to remove green algae from wood deck today. There’s some good news. Wooden decks developing green algae, fungus, and mold is common and can be easily fixed. Today, we’ll show you how to remove green algae from wooden deck along with a summary of the most effective tools to strip it away with.
While it’s possible to remove the algae from the deck, theres no way to fully prevent it from coming back again. This is just one of the issues owners face with wooden decks. Fortunately, proper care and maintenance can keep the algae at bay to some extent.
Be sure to complete this task as needed. Otherwise, the green algae and mold can rot the boards of your deck. This will create far more work in the long run than regular preventative maintenance.
Preparing the Deck
The first thing you need to do is thoroughly clean your deck. Using a regular broom, thoroughly sweep your wooden deck. Be sure to get the edges where the deck meets the house as well as the point where the railings touch the deck. Remove as much dirt and debris as you can. If you have a leaf blower, you can use this to clean the debris off the deck faster.
You can opt to rinse the deck with a garden hose at this point. You could also use a power washer. Sometimes, a first cleaning may remove most of the algae and it may look like the problem is solved but keep at it because a small, invisible layer of algae may remain and it will grow back quickly.
Cleaning the Deck
The best way to remove green algae from a wood deck is with a high-quality deck cleaner. These products are used to loosen dirt that has been ground into the wood fibers. They also help to remove other debris and gunk from the deck’s surface. There are plenty of different deck cleaners on the market, and you should choose one that’s specifically engineered for treating mold or green algae. This will be more effective than an all-purpose cleaner.
The best deck cleaners used are oxygenated bleach wood cleaners and a power washer. Some recommend using chlorine bleach, but this could damage your wood and will certainly kill any vegetation surrounding your deck. An oxygenated bleach deck cleaner won’t damage your wood and when it’s diluted, it won’t harm any surrounding plants.
Start by getting the deck wet with a hose. This is an important step. Wetting the deck fills the pores with water so the cleaner will remain on the surface of the wood, where it needs to do the most work. Skipping this step will result in the cleaner soaking deep into the pores, which means it’s going to take longer to rinse the product out of the wood.
Once the deck is wet, mix wood cleaner with a 5-gallon bucket of water. Using cold water may take longer for the wood cleaner granules to activate and dissolve. Using water that’s too hot will cause the cleaner to activate too quickly and lose its effectiveness. Luke-warm water will give you the best results. Don’t worry, you can still use cold water, you just may need to stir it a little longer and wait a little longer for the wood cleaner to dissolve.
Ok, so your wood cleaning solution is dissolved and ready to use. You can apply this to your wood either with a pump-up garden sprayer, a mop, or a deck brush.
Allow the deck cleaner to remain on the deck for 15-30 minutes so it kills any remaining green algae or mold. Keep the wood wet with additional cleaning solution if it starts to dry out. If it dries, it will stop working. Allowing the wood cleaner to remain on the deck during this time will loosen up any old finishes as well as remove any graying, mold or mildew. Once the cleaning solution has had time to work, it’s best to rinse the deck with a pressure washer. This is the best way to bring an old wooden deck back to life. The wood cleaner will clean and loosen any old finishes and the pressure washer will remove what the wood cleaner loosened up. If you don’t have access to a pressure washer, you can always use a stiff bristle brush and some elbow grease. However, this will not be as effective as a pressure washer.
Rinse the surface of the wooden deck again with a garden hose to remove any brightener that has been left behind. Be sure to rinse the rails, steps, and any other surface where the brightener might have splashed. For this step, a garden hose works better than a power washer. You’ll want to rinse the deck with as much water as you can. A pressure washer will add air, and use much less water than a garden hose, so just give the deck a thorough rinsing with the hose.
Once the deck has dried out completely, inspect it once more to be sure you removed all the green algae. When you are satisfied, you can put all the furnishings, plants, and other fixtures back where they belong, or stain the deck.
If your deck seems prone to green algae build-up, you can clean your deck annually with this cleaning method to keep your wood looking great year round. You may consider staining your deck with a semi-transparent deck stain that will give it a nice finish as well as seal it to help prevent future mold and mildew growth.