Remove Algae Build Up From Stone Patios With A Simple Cleaning Solution

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It's not uncommon to observe algae build-up on concrete or stone patios. A combination of wet weather conditions, poor air circulation, shaded areas, and a flat, hard surface makes for the perfect environment for jelly-like algae or sprays of lichen to grow. And though it may not seem like a big deal other than looking a little shabby, there are a number of reasons why you'll want to remove it from the patio. Primarily, algae growth is a safety hazard for anyone who walks on it, as it effectively acts like a film that makes surfaces incredibly slippery. In order to avoid an unfortunate accident, particularly in an area where you might be entertaining guests, you'll want to get rid of the slippery stuff. Luckily, algae removal is simple, easy, and affordable with washing soda. 

For those unfamiliar with the material, you might be asking what is washing soda, and how do you use it? You may know it by other names — sodium carbonate, soda ash, or soda crystals. It's a powerful degreaser and cleaning solution that's commonly used as a surface cleaner in kitchens and bathrooms as well as an additive to laundry to brighten clothes. It often comes in powder form and resembles baking soda, however think of washing soda as a stronger version of baking soda with alkaline levels that help neutralize acidic dirt, grime, grease, and stains. On patios, washing soda's potency, combined with its gentle abrasiveness and reasonable price tag, makes it a simple solution for your algae removal needs.

Your first task before using washing soda to rid algae from your patio is to remove any large pieces of debris, including any bigger growth of moss on the stone. Once the area is adequately clear, wet the stones enough to be damp. From here, you can either mix a solution of water and washing soda together in a watering can to spray it onto the stone (2 tablespoons for every 4 cups of water) or you can apply the powder directly on the patio if you have a smaller outdoor space. If the latter, make sure to evenly distribute the washing soda in a thin layer. Allow the mixed solution or the powder to sit on the patio for several minutes (or even several days to bake it in), and once it's soaked in well, use a stiff bristle brush to scrub the algae layer away. It may require a bit of elbow grease, however, you'll notice your patio returning to its natural stone color and texture.

Once you're satisfied with your work, be sure to rinse the patio off with clean water. Avoid spraying the washing soda off into any plant beds or lawn spaces, though. It is a salt, after all, and its high salinity can dry up and kill off plants. Furthermore, if you have any decorative water features or ponds around the patio, be careful not to rinse washing soda off into them either since it can alter the pH balance of the water.

Washing soda is surprisingly versatile and can be used in a number of ways in your outdoor spaces. It's an all natural, green ingredient that's gentle enough not to damage most building materials during the cleaning processes. As an added bonus, it's quite inexpensive compared with many other outdoor cleaning methods like power washing. An 11-pound bucket of washing soda from the Hznxolrc Store will run about $35. It can also be used elsewhere around your house's exterior. For instance, it makes for a gentle and affordable algae removal solution for house siding that won't damage vinyl. You can also apply the same methods of cleaning to high-trafficked areas like stone pavers or driveways, providing even more bang for your buck.

Your garden can also benefit from washing soda. While it could potentially damage plants you want kept alive, its dehydrating properties can actually help combat and eliminate weeds by drying them out. Apply small amounts of the powder to the weeds' roots, remove the growth, and flush the soda crystals out with clean water. You can also combat weed growth between pavers in your garden or walk way with washing soda as well.