How To Remove Green Mildew From Deck? 5 Manageable Methods

If your deck seems green after high humid weather, it probably has green mildew on it. If you’re wondering how to remove green mildew from deck, then continue reading. 

It’s very unsightly to see your deck appearing green; add to that the slimy texture that can cause you to slip, which is dangerous. The best thing to do is remove this and let yourself have a clean deck.

how to remove green mildew from deck


Green Mildew On Deck

Green mildew on deck may not be mildew; instead, it could be mold. Mildew is an early stage of mold — hence, it can be termed green mold after fully growing and developing its green hue.

Mildew grows only on surfaces of substances, while molds can penetrate deeper than that. Both grow in moist and high humid conditions.

Look Mold says that green mold doesn’t refer to only one particular species of mold. It was categorized like this due to it emitting a greenish hue when observed.

The three most common molds that appear green are Aspergillus, Penicillium, and Cladosporium. This can grow in various things and places, such as spoiled food, walls, cabinets, and wet materials.

This kind of mold often grows on dampened wood, starting with dark spots and becoming fuzzy.

Wooden decks are organic material that attracts molds and mildews. With suitable conditions, it can become their home.

For additional information, see this article about practical ways on how to remove mold from deck yourself. In this article, you will see other molds that can grow on your deck.


Is green mildew dangerous?

Mildew and mold outdoors are less worrying than growing indoors because it decreases the circulation of spores and the possibility of spreading. But then, spores can still travel towards the inside of houses since the deck can be located adjacent to your home.

Breathing in these spores for a lengthy time can be very detrimental to health. It can trigger reactions like coughing, sneezing, itchy skin, headaches, and a problem with breathing.

Mildew wouldn’t kill you, but it can still cause deterioration to your health. So please don’t leave it aside and let it thrive and consider this seriously.

Before you continue to the next part, you might want to know this article first about what causes green mold. This can help in intercepting further growth of green mold after the removal.


Methods For Removing Green Mold/Mildew

Products and techniques that can remove green mildew can also remove mold, algae, and moss. Before proceeding with the removal, make sure you wear proper protective equipment not to risk your health — this includes gloves, eye protection, and a respirator. 

The following methods are the means that you can make use of:


Method #1. Detergent mixed with water

On a bucket, mix detergent with water. Use the mixture on the affected area, then scrub it with a brush before washing it with water.


Method #2. White vinegar

For this method, you would need vinegar mixed with water. Pour this mixture on a watering can or spray bottle. 

Sprinkle the mixture on the affected areas, and with a brush or broom, rub and brush the molds or mildews away. Finally, rinse the area with clean water.


Method #3. Baking soda

Start with mixing one cup baking soda with a gallon of water, apply this mixture to the afflicted area and scrub with a brush. Lastly, wash it clean with water.


Method #4. Hydrogen peroxide (3%)

Use a mix-up of hydrogen peroxide with equal amounts of water, place the solution in a spray bottle for more accessible application. Scatter the solution on the mold or mildew section, leaving it alone for 10 minutes before washing out the area with water.


Method #5. Pressure washer

When adding detergent to the power washer, be sure to follow the manual. Utilize the nozzle that comes with the soap dispenser for this. 

Starting at the farthest edge, apply the solution in a motion like sweeping. Fully clean the entire range; make sure to scrub the tough spots with a brush. 

After the application of the solution, broaden the nozzle, and sweep the area thoroughly. After that, wash the deck with clean water to remove the remnants.

It can be an incredibly demanding task to remove mold or mildew. So it is understandable if you are thinking of leaving the removal to a professional.

You can check out this article about what to know before hiring a mold remediation pro to assist you.



In order to cure the unsightly green mold or mildew on your deck, you need to know how to remove green mildew from deck. With the various ways stated earlier to help you, this task then would be easier.

Regardless of what color it is, this can still have a significant effect on your home. Possibly, you have moisture problems that need to be addressed as soon as possible if you see mildew and molds growing in any part of your home.

Don’t compromise your and your family’s health and take action.

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