How to Remove Algae and Fungus on Patios

Fungus and algae grow easily on patios that are shady, moist and are not kept free of dirt and debris. Whether the growths are green, black, gray or white, your patio will look ugly and dirty, and may even be slippery, as long as fungus or algae remain. You can rid your patio of these unsightly growths with a bit of work. After you’ve cleared your patio, you can keep algae and fungus away through regular cleaning.

Things You'll Need

• Garden hose or pressure washer
• Bucket
• Push broom
• Dust pan or shovel
• Rubber gloves
• Safety glasses
• Detergent containing an algae and fungus killer
• Mop

Instructions

1. Spray the patio with water from your garden hose or pressure washer only on lower pressure. Alternatively, if you do not have access to a garden hose, you can pour water from a bucket to wet the patio, according to PaverSearch.com.

2. Use a push broom to sweep away surface grime from the patio. Sweep loosened algae, fungus and other debris into a dust pan or shovel for easier disposal. Dispose of this debris in the garbage—not your compost pile—to avoid contaminating compost with fungus.

3. Put on rubber gloves and safety glasses. Mix a detergent containing an algaecide and fungicide with water in a bucket. Look for these special detergents at home improvement stores in the lawn and garden sections. If you are concerned about staining or discoloration of your patio, PaverSearch.com suggests using a small amount of the cleaner to test a small spot before cleaning the whole area.

4. Use a mop to spread the solution over the patio surface. Some cleaning solutions may require time to effectively kill fungus and algae. Follow directions on the label.

5. Scrub the patio with your push broom. Rinse the patio well with water from your garden hose or a bucket; you can empty the mop bucket and refill with clean water.

Tips & Warnings

• If you use a pressure washer, hold the wand at an angle, and move it in a sweeping motion so the water’s force doesn’t remain against a small surface for longer than necessary.

• Although using a pressure washer is popular, be very careful. The forceful stream of water from power washers easily discolors brick or degrades paving stones and even concrete.

References

• Demesne: Maintaining and Cleaning Brick
• PaverSearch: Pavers Cleaning Procedures