How to Clean a Polyester Gazebo Canopy


Buckley asked: The gazebo has been out all summer and is located under trees. The polyester material is stone colored, but is stained black. I don’t know whether it’s mildew or just dirt. I tried washing it at 40 degrees with non-biological detergent, which made absolutely no difference whatsoever. Any suggestions?

The black discoloration could be from a variety of things. The shade from the trees makes an excellent location for mildew to form. Trees also deposit all kinds of pollens and dirt that can settle and collect over time. In many cases, it becomes a mix of the two. Cleaning this black growth will take some time and effort but can be done with good results. Here are the steps and cleaning products needed for success.

You Will Need:

  • Mild detergent
  • Soft haired broom
  • Sponges
  • Buckets
  • Soft towels or cloths
  • Hose

Steps to Clean the Canopy:

  1. Fill the bucket with warm water and add mild detergent. The dirtier the canopy, the more soap that will be required.
  2. Agitate the water until it is mixed completely and suds begin to form.
  3. Dip a soft haired broom into the soapy water and brush it onto the canopy.
  4. Scrub gently with the broom to remove the mildew and stain build up.
  5. For stubborn areas, moisten a sponge with the soapy water and scrub carefully.
  6. After cleaning, rinse the cover completely to remove all of the soap residue.
  7. Repeat as necessary until the dirt and stains are removed to your satisfaction.
  8. Allow the canopy to dry completely. In the sun is preferred, if possible.

Additional Tips and Advice

  • Removing sap and dirt immediately (or at least on a regular basis) will make cleaning much easier and more effective.
  • For mildew, a mild bleach/water mixture will help to kill and remove the mold spores.


  1. Raquel says:

    The tips to clean the Gazebo were AMAZING!! We are waiting for it to air-dry and we will pack it till next year!

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