Outdoor rugs are a great way to add style and comfort to patios, decks, and porches. However, being exposed to the elements can cause mildew and mold to grow on outdoor rugs, especially in damp climates. Mildew stains not only look unsightly, but the spores can also pose a health hazard if left untreated. Fortunately, there are several effective methods for removing mildew from outdoor rugs to restore their appearance and safety.
What Causes Mildew on Outdoor Rugs?
Mildew is a type of mold that grows on damp surfaces. The main culprits that cause mildew growth on outdoor rugs are:
- Moisture – Wet weather, sprinklers, rain, and excess humidity provide ideal conditions for mildew spores to thrive.
- Lack of sunlight – Shady areas prevent an outdoor rug from fully drying out, allowing moisture to linger.
- Poor ventilation – When outdoor rugs are placed in enclosed spaces without airflow, moisture gets trapped.
- Organic materials – Natural fibers like cotton, jute, sisal, and wool readily absorb moisture, creating a breeding ground for mildew.
Mildew typically appears as grayish-black spots or powdery colonies on the surface of the rug. It can be difficult to remove if left for too long.
How to Prevent Mildew Growth on Outdoor Rugs
Prevention is the best way to avoid mildew from forming on outdoor rugs. Here are some tips:
- Allow the rug to dry out completely between uses by placing it in direct sunlight.
- Improve airflow by flipping the rug periodically and avoid enclosing it tightly on a covered patio.
- Vacuum both sides of the rug regularly to remove surface dirt and spores.
- Spray the rug with an anti-microbial treatment to inhibit mold and mildew growth.
- Blot spills and wet spots quickly to prevent moisture from seeping deep into the fibers.
- During damp weather, consider rolling up and storing the rug until conditions improve.
- At the end of the season, clean the rug thoroughly before storing to prevent off-season mildew growth.
How to Remove Existing Mildew from Outdoor Rugs
If mildew has already taken hold on your outdoor rug, don’t worry. Here are some effective ways to tackle the problem:
Baking Soda Scrub
Baking soda is mildly abrasive and alkaline, which helps destroy mildew and neutralize odors.
What You Need:
- Baking soda
- Warm water
- Scrub brush or sponge
How To Do It:
- Vacuum the rug thoroughly to remove loose spores and dirt.
- Liberally sprinkle baking soda all over the affected area. For heavier mildew, first dampen the area before adding baking soda.
- Using a scrub brush or sponge, gently rub the baking soda into the rug fibers.
- Let it sit for 2-3 hours. The baking soda will continue working to lift the stain.
- Vacuum the rug again to remove all the baking soda along with mildew residues.
- Allow the rug to dry completely in direct sunlight.
For severely affected areas, repeat this process focusing on the spots until no stain remains.
Vinegar Solution
The acetic acid in vinegar kills mold and mildew while helping dissolve stain residues.
What You Need:
- White vinegar
- Warm water
- Clean cloth or sponge
How To Do It:
- In a bucket or spray bottle, mix equal parts white vinegar and warm water.
- Apply the vinegar solution liberally over the mildewed area. For concentrated spots, spray directly over them until saturated.
- Gently blot the mildew stains using a soft cloth or cleaning sponge. Avoid aggressive rubbing.
- Allow the vinegar solution to penetrate for 15-20 minutes. Rewet if it starts to dry out.
- Rinse with clean water and blot dry. Make sure no vinegar residue remains.
- air dry the rug in direct sunlight to prevent re-growth.
Repeat as needed for stubborn mildew stains. The vinegar smell will dissipate once the rug dries.
Hydrogen Peroxide Solution
Hydrogen peroxide is a mild bleach that kills mold spores on contact. When used in moderation, it whitens without damaging outdoor rug fibers.
What You Need:
- 3% Hydrogen Peroxide
- Warm Water
- Clean Cloth or Sponge
- Bucket
How To Do It:
- In a bucket, dilute 3% hydrogen peroxide with an equal amount of warm water.
- Dip a clean cloth into the solution and blot the mildewed areas to saturate them fully.
- Let it sit for 10-15 minutes to allow the peroxide to bubble and work on the stain.
- Blot with clean water to rinse. Make sure no peroxide residue remains.
- Allow the rug to air dry completely before reuse.
For heavy mildew stains, repeat the process as needed until the stains are lifted. Rinse thoroughly between applications and dry the rug in sunlight.
Lemon Juice Solution
Like vinegar, lemon juice contains citric acid that kills mildew spores and helps remove stains. Its bleaching powers also restore brightness.
What You Need:
- Fresh lemon juice
- Warm water
- Clean soft cloth or sponge
- Bucket
How To Do It:
- Squeeze enough lemons to extract 1 cup of fresh lemon juice.
- Add the lemon juice to a bucket containing 1 cup warm water.
- Dip a cloth into the solution and blot the mildewed areas thoroughly.
- Allow the solution to soak in for 20 minutes. Re-apply if it starts to dry.
- Rinse with clean water. Blot away excess moisture.
- Allow the rug to dry fully in direct sunlight.
The natural bleaching action of lemon juice will help lift the stain over repeated applications. Rinse thoroughly after each application.
Oxygen Bleach
Non-chlorine oxygen bleach effectively destroys mildew and whitens outdoor rugs without the harshness of chlorine bleach.
What You Need:
- Oxygen bleach powder or liquid
- Warm water
- Bucket
- Clean cloth or sponge
How To Do It:
- Check the label instructions and dilute the oxygen bleach powder or liquid with warm water.
- Apply the solution over the mildewed area using a cloth or sponge. Ensure full coverage.
- Let it soak for 10-15 minutes. Reapply if needed.
- Rinse thoroughly with clean water until all bleach residue is removed.
- Allow the rug to dry completely in direct sunlight.
Oxygen bleach may need several applications to fully lift heavy mildew stains. Rinse well after each application.
Borax Solution
A solution of borax in hot water effectively kills and removes mildew. The alkaline borax also deodorizes the rug.
What You Need:
- Borax powder
- Hot water
- Bucket
- Clean cloth or sponge
How To Do It:
- Add 1⁄2 cup borax powder to a bucket of hot water. Stir to dissolve.
- Dip a clean cloth in the solution and blot it thoroughly over the mildewed area.
- Let it penetrate for 15 minutes, reapplying if needed.
- Rinse several times with clean water to remove all borax.
- Blot excess moisture and allow to dry completely in the sun.
Repeat for stubborn stains. Rinse borax thoroughly as residue can damage fibers over time.
Wet Vacuum Treatment
For quick cleaning of overall mildew before deeper cleaning, a wet vacuum can lift surface mold and spores.
What You Need:
- Wet/dry vacuum
- Rug shampoo solution
How To Do It:
- Mix a mild rug shampoo in hot water per label instructions.
- Wet the entire surface of the rug with the shampoo solution using a sponge or sprayer.
- Go over the rug back and forth with the wet vacuum to extract the milky solution along with spores.
- Rinse with clean water and repeat the vacuuming until no more suds emerge.
- Let the rug dry thoroughly before placing it back outside.
The hot sudsy water helps loosen mildew spores from the fibers while vacuuming lifts them away for quick cleaning.
Bleach Gel Treatment
Using a thick bleach gel keeps the bleach in contact with the mildew to kill mold spores without damaging the rug.
What You Need:
- Chlorine bleach gel or thickened bleach
- Plastic wrap
- Rinse bucket
How To Do It:
- Cover your hands with gloves and apply the bleach gel liberally over the mildewed area.
- Spread plastic wrap over the gel to keep it from drying out.
- Let it sit for 1-2 hours, reapplying gel if needed.
- Remove the plastic. Rinse the rug thoroughly with clean water to remove all bleach residues.
- Blot excess moisture and allow to dry fully in direct sunlight.
The thick gel targets the mildew stain while protecting the surrounding fibers from bleach damage.
Mildew Remover Spray
Specialized mildew remover sprays quickly penetrate and eliminate mildew stains.
What You Need:
- Mildew remover spray
- Scrub brush
- Clean water
How To Do It:
- Shake the bottle well and spray liberally over the mildewed area.
- Allow it to soak in for 10-15 minutes. Respray if needed.
- Scrub rigorously with a brush to lift the stain from the base of the fibers.
- Rinse clean and blot away excess moisture.
- Air dry in sunlight.
These sprays make light work of surface mildew spots. Follow with other methods for deeper mildew stains.
Professional Hot Water Extraction
For extensive mildew damage, professional hot water extraction cleans thoroughly by flushing away mildew from the rug roots.
How It Works:
- The rug is pretreated with an antimicrobial solution.
- Hot water is forced into the rug under pressure to penetrate the fibers.
- A powerful wet vacuum immediately extracts the dirty solution.
- The rug is rinsed and dried thoroughly.
Hot water extraction removes embedded mildew that other DIY methods may miss. Professional cleaning is recommended for rugs with advanced mildew growth.
How to Dry and Prevent Mildew After Cleaning
Proper drying and prevention after mildew removal is key to ensuring the mildew doesn’t quickly return.
- Allow the rug to dry completely before placing it back outside. Use fans to speed drying.
- Vacuum well once fully dry to remove any remaining spores.
- Consider spraying the rug with an anti-mildew treatment to inhibit regrowth.
- Improve ventilation and air circulation wherever placing the rug.
- Blot spills and rinse frequently to avoid moisture accumulation.
- Bring indoors during rainy periods to allow thorough drying.
- At winter storage, clean and apply anti-mildew spray for off-season prevention.
With proper prevention and prompt cleaning methods, you can keep your outdoor rug free of ugly mildew stains all season long.
Frequently Asked Questions about Removing Mildew from Outdoor Rugs
Can I use chlorine bleach to remove mildew from outdoor rugs?
Yes, you can use chlorine bleach to kill mildew on outdoor rugs. However, it’s important to use it cautiously to avoid damaging the rug fibers. Test for colorfastness first. Opt for thick gels or sprays that target the mildew without harming the rug itself.
What temperature water should be used when cleaning mildew from outdoor rugs?
Warm to hot water is ideal when cleaning mildew from outdoor rugs. The heat helps to more effectively kill mold spores and loosen stain residues from the rug fibers. Always rinse with clean water to remove treatment residues.
Can I clean mildewed outdoor rugs at home or do they require professional cleaning?
You can clean mild mildew from outdoor rugs at home using methods like vinegar, baking soda, or oxygen bleach. For advanced mildew growth, professional hot water extraction is recommended to deep clean embedded mildew that has spread to the rug’s roots.
How can I stop mildew from growing back after cleaning outdoor rugs?
To prevent mildew from recurring after removal, ensure the rug dries fully in sunlight before placing it back outside. Improve ventilation, use anti-mildew sprays, clean spills promptly, and bring it indoors when damp. Proper drying and prevention are key for controlling mildew.
What is the best way to dry an outdoor rug after cleaning mildew or spills?
The best way to dry an outdoor rug is to lay it flat in direct sunlight. Turn it over periodically to ensure both sides dry fully. Use fans to improve air circulation and speed drying. Do not replace on patios or decks until completely dry to avoid re-growth of the mildew.
Conclusion
Mildew and mold growth are common problems with outdoor rugs exposed to moisture and damp conditions. Left untreated, mildew can become deeply embedded in the rug fibers and lead to permanent stains and odors. By understanding what causes mildew and learning how to both prevent and remove it safely, you can keep outdoor rugs fresh, clean, and mildew-free all season long. Using natural methods like lemon juice and vinegar solutions, oxygen bleaches, or commercial mildew removers and taking proper drying precautions can restore the beauty and longevity of prized outdoor rugs. With proper care and prompt treatment, outdoor rugs can maintain their good looks for many seasons.