It is best to use a mild brush and scrub off all of the outdoor furniture before doing anything else. Try to get out all of the dirt and grime out of the outdoor furniture using the brush. You can also give your outdoor furniture a nice wash with some water. Be sure to do this in the sun so that your furniture can dry up properly before applying any other substance on it to remove the mold.
Put about ½ gallon of water in your empty spray bottle with about ¼ cup of bleach. Spray the outdoor furniture with this mixture and use your sponge or brush to wipe off the mold. Apply a little amount of the bleach mixture on a part of the outdoor furniture that you cannot see to make sure that it does not remove the colour. Remember to take your time and allow the bleach to work. Bleach is a good solution to use to remove mold but it can be quite harsh on your outdoor furniture. Be sure to thoroughly rinse off the outdoor furniture of any bleach after you are done cleaning.
Use Baking Soda:
You can use a little baking soda with your wet sponge to gently clean mold from your outdoor furniture. This is relatively easy and not as harsh on the outdoor furniture because the baking soda is ideal for cleaning mold.
Mix a small amount of vinegar with baking soda and use your sponge to apply this mixture to your outdoor furniture. Vinegar is excellent for removing mold from your outdoor furniture. You will find this solution much better than bleach as it is mild and easy to do.
If you do not have the time and a little bit of extra cash then you can always hire a professional cleaner to come to your home and clean all of your outdoor furniture properly.