How to Remove Mold and Mildew From Outdoor Cushions

The safe, effective method for removing black mold and mildew from patio chair and lounge cushions.

Outdoor cushions are the most mold-prone item in your backyard. Moisture, heat, and organic debris (pollen, food, dirt) create ideal growing conditions. Mold on outdoor cushions is a health concern and can permanently damage the fabric if left untreated. Here’s how to remove it completely and prevent it from returning.

Is It Mold or Mildew?

Mildew appears as white or gray flat patches — surface-level and easier to remove. Mold appears as black, green, or fuzzy clusters and may have penetrated deeper into the cushion fill. Both need treatment; heavy black mold may have permanently stained the fabric.

Safety First

Wear gloves and if possible a mask when handling moldy cushions
Take cushions outdoors before treatment — don’t clean moldy items inside
Brush off loose mold spores outside and away from air intakes before washing

Method 1: White Vinegar (Safe, Natural)

Vinegar Method

Brush off loose mold with a stiff brush (outdoors)
Spray undiluted white vinegar on all affected areas
Let sit 1 hour — vinegar kills approximately 82% of mold species
Scrub with a stiff brush
Rinse with clean water
Apply vinegar again and let dry in direct sunlight — UV kills remaining spores

Method 2: Bleach Solution (Most Effective on Severe Mold)

Check fabric label — avoid bleach on colored fabrics (will fade)
Mix: 1/4 cup bleach + 1/4 cup dish soap + 1 gallon warm water
Apply with a brush, scrub affected areas
Let sit 15 min
Rinse very thoroughly — bleach residue degrades fabric over time
Dry in direct sunlight

Removing Mold Stains After Treatment

Even after killing the mold, dark staining may remain:

Apply OxiClean paste to remaining dark areas, let sit 30 min in sun
Scrub and rinse
Repeat if needed
Deep-set black stains in fabric are often permanent — accept lighter discoloration as the ceiling of improvement

Preventing Mold from Returning

Store cushions in a ventilated deck box or garage when not in use — not covered with a tight tarp
Allow cushions to dry completely after rain before covering
Apply a fabric protector spray (Scotchgard) to create water-repellent barrier
Stand cushions on their edge after rain so both sides drain and dry

Sunshine is your best ally: UV light from direct sunlight kills mold spores more effectively than most household cleaners. After any mold treatment, dry cushions in full direct sunlight for at least 4–6 hours before storing.

My cushion foam inside is moldy — can I save it?

If mold has penetrated to the foam insert, it’s extremely difficult to remove completely. The foam can be treated by soaking in a diluted bleach solution (1:10 ratio) and squeezing to force liquid through. Rinse thoroughly and dry completely in the sun. If the foam smells moldy after drying, it should be replaced — inhaling mold spores from a moldy cushion is a health risk.

Full Outdoor Cleaning Service

Professional patio and outdoor furniture cleaning available across the US.

Get a Quote →