4 Easy Ways to Remove Mildew Stains from Outdoor Cushions

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Mildew is a common issue with many outdoor furniture. When you notice the discoloration on your cushions, your first instinct might be to pull out some bleach.

However, bleach is a harsh chemical that can damage the fabric and can pose safety risk to the person using it. Knowing that, you’re probably wondering how to remove mildew stains from outdoor cushions without bleach.

Luckily, there are plenty of safer alternatives that can help remove mildew stains with minimal damage to your furniture. These gentler cleaning methods can help extend the life of your cushions.

Interested in finding out more? Let’s dive in!

Identifying Mildew Stains on Outdoor Cushions

Mildew is a type of fungal growth that tends to infect organic substances. Generally, it thrives in damp, dark areas that have poor ventilation.

However, that’s not always the case. This species can also multiply by spreading its spores through the air. Then, after the tiny particles land, they’ll start to look for food and water.

Unfortunately, your outdoor cushions are a perfect resting place for these spores. First off, outdoor furniture is usually left in the backyard, exposed to the elements.

Chances are, it’ll get wet from dew, humidity, and rain. On top of that, the cushion fabric provides the spores with the nutrients they need to grow and multiply.

So, the first part of removing mildew from cushions is recognizing what it looks like. You can do that by keeping an eye out for some physical characteristics.

Typically, mildew will appear chalky white with a smooth, flat surface. Yet, over time, the color can shift to a grayish brown. In addition, areas with mildew will give off a stale, musty odor.

Removing Mildew Stains From Outdoor Cushions

When you’re thinking about removing any persistent stains, a bleach-based cleaning agent is usually the go-to solution. Bleach is a powerful chemical that can eradicate any blotch. Yet, it’s not always the best course of action.

As we mentioned, the mildew feeds on the cushion fabric. This can significantly impact the tensile strength of the cloth.

So, even applying diluted bleach may harm the fabric, causing it to deteriorate. For this reason, you’ll want to take a gentler approach.

Let’s take a closer look at the steps you need to follow to get rid of mildew.

Step 1: Taking Safety Precautions

You have to remember that even though it looks harmless, mildew can be dangerous. When the fungus releases its spores, it can land on any surface. Unfortunately, this also means you.

Sadly, that means the infection can spread from furniture to humans. In some cases, the spores can cause respiratory infection if inhaled.

So, taking safety precautions is key to avoiding a trip to the clinic.

First off, you’ll want to make sure you wear protective gloves. This will prevent your hands from getting in contact with the mildew.

More importantly, a face mask will prevent spores from entering your airway.

Still, even with gloves and a mask, you must work in a well-ventilated area.

Step 2: Prepping Your Outdoor Cushions

Mildew has a pretty high multiplication rate, and unless you remove every trace, the mold can easily grow back.

So, before you attempt to remove mildew, you should ensure it’s not actively growing. The easiest way to do that is to remove its source of nutrition: moisture.

You can do this by placing the cushion in direct sunlight for a few hours. It’s best to do this outdoors, where there’s more airflow that can help the fabric dry out faster.

Step 3: Choosing an Ideal Removal Process

When your cushions are fully dry, kick off the cleaning process.

Citrus and Salt

One of the most common methods of removing mildew uses two household items: citrus fruit and salt.

The acid in the citrus should break down the mildew, while the salt acts as a scrub. To get the best results, use fresh citrus juice and coarse salt.

Start with about half a cup of citrus juice. Then, slowly add salt to the liquid until it forms a paste. The final product should have a smooth but slightly grainy consistency.

Once you have your paste, you can gently rub it into the mildew patch. The best tool for this job is a toothbrush.

After a few minutes of scrubbing, slowly pour water over the paste. Your goal here is to dissolve the mixture. Finally, rinse the cushion with plenty of clean, warm water, and set it out to dry. 

The greatest advantage of this method is that your cushions will smell tangy and fresh for a while.

Baking Soda

Most of us are familiar with baking soda’s amazing cleaning abilities. It easily removes stains with minimal effort.

Since baking soda is an alkali, it can eat away at substances like dirt, grease, and, of course, mildew.

To begin, cover the cushion with a thin layer of baking soda and set it aside. While that’s resting, you can mix up the cleaning solution.

To do that, combine two cups of water with two teaspoons of baking soda.

After 15–20 minutes, you’re ready to scrub. Start by sprinkling a small amount of the solution over the infected cushion.

Moving in circular motions, scrub off the mildew with a toothbrush until it starts to fade. Then, rinse out the cushion with warm water.

It’s worth mentioning that this method may take slightly longer than citrus and salt. So, you may have to repeat this process a few times to thoroughly clean the cushion and remove any traces of mildew.

In addition, baking soda can leave behind a musty scent. However, there are a couple of ways to get rid of the aroma.

The best way to do that is to leave the cushions in the sun for a few hours. Then, if that doesn’t do the trick, run them through the washer a couple of times.

White Vinegar

White distilled vinegar is a jack of all trades around the house –it’s not only used for cooking, but is a universal cleaning agent. One of the great benefits in using vinegar is that it is non-toxic and is a safe alternative to bleach.

Although there are many types of vinegars on the market, choosing white vinegar will not stain fabric like other colored vinegars might.

Simply fill a small container with white vinegar. Dip a soft bristled brush into the vinegar and then scrub the mildew.

Dampen a cloth or paper towel with white vinegar and lay it on the treated area. Allow it sit for 10-15 minutes.

After the mildew stains have disappeared, allow the cushions to air dry.


Even though some of the other treatments can often be effective, they require a good amount of elbow grease.

Sodium borate is a chemical that can dissolve dirt and mildew. It also acts as a disinfectant, which can reduce the chance of mold re-growth.

Unlike the other two methods, it’s best to start this one with a wet cushion. 

Soaking your cushion in clean water for a few minutes beforehand will help the borax penetrate the fabric all the way through.

For this process, you’ll need a cleaning detergent that contains borax. Fill a bucket with warm water and add about two cups of detergent.

Then, using a scrubbing brush, dip it into the solution and apply it to the cushion. After a couple of minutes, rinse out the cushion and leave it to dry fully.

The borax method is excellent for deep infections. Because of the water soak, the chemical penetrates the fabric much deeper, allowing for the removal of all traces of mildew.

However, borax can be a little dangerous. It can cause mild skin irritations and, in some cases, allergic reactions. So, it’s important to wear gloves and a face mask to keep yourself out of harm’s way.

Final Takeaway

Determining how to remove mildew stains from outdoor cushions without bleach is simple. It’s all about finding a suitable replacement.

The most common method is a mixture of citrus and salt that helps remove mildew and leave your cushions smelling amazing.

You can also use baking soda or vinegar as other safe treatment options; however, they’re not always aggressive enough to totally eliminate the stains.

Fortunately, borax is often the best solution for removing deep mildew growths without using bleach. However, the chemical is an irritant, so use it with caution.

Now, with the help of our handy guide, you’re ready to get rid of mildew once and for all!

Happy Cleaning!

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