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How To Keep Outdoor Curtains From Mildewing

We’ve heard horror stories about outdoor curtains that get mildew. But what is it doing to the fabric? If you’ve got a curtain that’s showing signs of mildew, it’s time to take some action. We have researched this, and we are going to share the best solutions for treating mildew in curtains so you don’t have to worry anymore.

Disclosure: We may get commissions for purchases made through links in this post.

A recent study by the University of Michigan found that using an anti-mildew spray could significantly prevent and reduce mold growth. Anti-mildew sprays contain fungicides that will kill or inhibit mold and mildew growth. You can also keep outdoor curtains from mildewing by keeping them clean and damp-free, but this would mean checking on them every once in a while.

We’ve all had to deal with those annoying outdoor curtains and draperies that are mildewing just because we left them outside for the summer months. This situation can be avoided by taking simple precautions before hanging them up for the season. Let’s look at the steps you can take to prevent and remove mildew, so read on!

Outdoor cafe dining with a hillside lean, rustic table and chairs under a mildewed tent, How To Keep Outdoor Curtains From Mildewing

What Is A Mildew?

Mildew is a fungus that grows on organic material such as decaying vegetation, plant life, and fabric. It can also grow on non-organic materials such as walls, window frames, floors, or even furniture. Mildew doesn't necessarily need to grow on organic material to cause damage. It can be introduced into a home by people or pets through airborne spores.

Fungal mildew

A common misconception about mildew is that it's something that only occurs outdoors. In reality, it's quite possible to find mildew indoors. The spores that cause mildew may have entered the house in several ways.

What Causes Mildew To Grow And Develop?

The growth of fungi or mold causes mildew. The fungi usually come from the air, and they grow on surfaces where water is abundant. Mildew is generally not harmful, but it is unsightly and can cause odors.

How To Make Outdoor Curtains Mildew-Resistant

If you think your curtains have mildew on them, you're probably right. Mildew is easy to prevent and get rid of, and we've looked into the best ways

1. Make sure your curtains are pulled apart and properly ventilated during daytime

 The problem with curtains is that they can trap moisture and heat inside your home. This causes the air to become moist and warm, which is ideal for mold and mildew growth. Keeping your curtains open during the day will help to release some of this trapped moisture.

2. Avoid using water-based cleaners for very obvious reasons

When washing your curtains, you don't want to run into the situation where you end up with a bunch of damp spots and a mess of a freshly-washed curtain. In other words, it's not recommended to wash heavy blackout curtains when the season is humid unless you have a powerful dryer that is up for the task.

In addition, an alcohol-based cleaner is much preferable to a water-based one because we are trying to prevent mildew growth here.

For curtains that are already washed, the easiest way to keep them from sticking together is to hang them in the open sunlight. When hanging, consider the amount of space between the folds, as this is the only way to ensure the curtain has sufficient airflow and doesn't stick to itself.

3. Apply anti-mildew spray on curtains

Anti-mildew sprays have a thin, fine mist allowing complete coverage of your curtain's fabric. The fine mist also makes it easy to apply the spray evenly.

To apply the anti-mildew spray to the curtains, spray the curtain and let it air dry for a few minutes. It can be applied to both cotton and synthetic fabrics. Anti-mildew spray can also be used on drapes, shades, and other window treatments.

When you purchase an anti-mildew spray, you'll find that the label will have a recommended application time for the product. Follow the instructions on the label to ensure that you're getting the most out of your spray.

You can also follow the steps in this video to make your outdoor curtains mildew-proof:

Check out this anti-mold and mildew spray on Amazon.

Home Remedies For Removing Mildew

If you're not a fan of synthetic, commercial anti-mildew solutions, you may want to try one of the natural remedies below:

1. White Vinegar

White vinegar

For a DIY mold treatment, simply fill a spray bottle with white vinegar. Spray the vinegar on the curtain and let it sit for at least an hour, allowing the vinegar to soak into the fabric. But if your mold is particularly stubborn, you can also use baking soda solution to scrub it off. The baking soda solution should be one teaspoon mixed with 2 cups of water.

Spray the solution and gently scrub the affected area with a soft brush until you see the molds fading away. Alternatively, mix two teaspoons of tea tree oil with two cups of vinegar for a more potent solution. 

2. Hydrogen Peroxide

Hydrogen Peroxide

Hydrogen peroxide is effective at killing mold spores. Not only does it kill the mold itself, but it also prevents the mold from growing. It does this by causing the mold spores to lose their potency and thus can no longer multiply on the surface it is sprayed on (but for a limited period, of course). Hydrogen peroxide works by disrupting the integrity of the cell walls of molds, causing the cells to leak and die.

To make mold remediation using hydrogen peroxide, simply make a spraying solution. Spray it on the curtain's surface and let it penetrate the fabric for at least 15 minutes. Wipe it off and repeat as needed.

Check out this hydrogen peroxide on Amazon.

3. Lemon Juice

Lemon juice

Lemon juice is an all-natural, safe and inexpensive method to remove mold and mildew stains from curtain fabrics. To use lemon juice to clean mold, follow these simple steps:

  1. Clean and dry the area to be cleaned by mild soap and water. Rinse and dry.
  2. Squeeze some lemon juice and put it into a spray bottle.
  3. Spray the area to be cleaned until the mold begins to disappear. Let it sit for a few minutes.
  4. Scrub the area with a soft brush.

4. Grapefruit Seed Extract

The grapefruit seed extract is a natural, nontoxic cleaner for hard and soft surfaces. To make your own grapefruit seed extract mold remediation, mix a 10:1 solution (10 drops of extract to 1 cup of water).

Spray it on the mold as often as needed. You can also apply the solution to the mold with a cotton ball. Let it sit for a few minutes.

Check out this grapefruit seed extract on Amazon.

5. Color-Safe Bleach

Pour some bleach

Bleach is an effective but caustic cleaning agent. It is an oxidizing agent that is strong enough to break down certain proteins, including those found in fabric. This means that it can damage the fibers of your clothes if you aren't careful. It can also damage clothing if you use too much. So you'll want to be sure that you use it in moderation and the right areas.

To dilute bleach, add enough water to a container to create a solution of 1 part bleach to 4 parts water. Once you've diluted your bleach, spray the solution on the curtain. Spray from a distance just enough for the mist to reach the fabric. Generally, you want to avoid applying bleach directly to anything except when used to remove stains.

It's best to cover the entire fabric with a thin layer of bleach solution. Then, let the bleach solution sit for 15 minutes.

Check out this color-safe bleach on Amazon.

Recommended Fabric For Outdoor Curtains

Olefin fabric is a durable, tough fabric resistant to the sun's ultraviolet rays. It's also available in a wide range of colors, styles, and patterns, making it easy to find a fabric that perfectly fits your needs. The Olefin fabric is made up of polypropylene, a polymer that's generally considered safe to use. It's also soft enough to drape gracefully without feeling scratchy.

However, it's important to note that while the Olefin fabric is resistant to UV rays, it's not completely waterproof (although some of them are).

How To Add Weights To Outdoor Curtains

The trick to adding decorative but functional weights to your curtains is to create something that won't fall off, and that's not going to get caught in the wind.

For a simple and effective solution, you can sew an M12 or M20-sized washer onto the bottom seam of your curtains. If you're more crafty, you can attach the washers to the outside of the curtains or make them hang from the edge.

Outdoor Curtains Touching The Ground: Is It A Good Idea?

Outdoor living with a beautiful view

If you are always bothered with constantly moving the outdoor curtain, you need a curtain that easily opens and closes without getting caught on the hardware. An anti-rust grommet is a perfect solution for this. You also want to ensure the curtain edges are off the ground a few inches so you won't have to deal with dust collected on the floor.

In Closing

Keeping your curtains dry and well-ventilated during summer is the most basic and most important rule of thumb for keeping them mildew-free. However, who has the time to check on them every once in a while? Just get an anti-mildew spray on your curtains to make life easier!

Nevertheless. we have shown in this article some helpful tips and tricks to help you keep your outdoor curtains in top shape and ready for summer. So, the next time you think about moving them out of the way for cleaning: just do it right and enjoy summer!

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