Concrete is an attractive, durable material for constructing decks, patios, driveways, porches and walkways. If you’ve had concrete installed around your home, you’re probably pleased with the results… and your wallet was probably much lighter after the work was done. The last thing you want to see is staining from algae, lichen, moss, mold or mildew turning your costly investment into an ugly mess and causing a slippery hazard for anyone walking on it. Let Wet & Forget Outdoor take care of the concrete stains for you. No pressure washer or elbow grease required!
Step 1: Identify the Stain
Before you tackle the stain, it’s important to know which type of concrete stain you’re dealing with. Here are descriptions of the common culprits:
- Moss: Moss is a fuzzy, green, velvety growth that can resemble a green carpet in severe cases (see photo). Moss isn’t only ugly–it also has tiny root-like structures that can cause pitting in concrete, which can permanently scar the surface.
- Algae: Algae is a simple plant that can grow on just about any outdoor surface. It can be slimy, especially when wet–this makes it a slippery danger on walkways. Algae is generally green, or a brownish or reddish black. Green algae grows in areas of shade or partial shade, and black algae can grow in full sun.
- Mold and Mildew: “Mold” and “mildew” are both names for fungal growth. Mold and mildew can be slimy or fuzzy, and is often black, but can also be white, gray, green or rust-colored. These growths usually thrive in damp, shady areas.
- Lichen: Lichen is a multi-layered growth that is formed through a symbiotic relationship between fungus and algae. It can grow on almost any outdoor surface, and has been found growing on every continent, including Antarctica. Lichen comes in a rainbow variety of colors, and is easiest to recognize by its scaly texture.
Step 2: Apply Wet & Forget Outdoor
To treat your concrete with Wet & Forget Outdoor Concentrate, mix a solution of 5 parts water and 1 part Wet & Forget Outdoor in a pump-up garden sprayer, then follow the directions below. For large concrete surfaces, attach the Wet & Forget Hose End product to your garden hose and attach the fan tip, then follow the instructions below.
- For Moss:
Spray the affected area with diluted Wet & Forget Outdoor at a time that allows 4 to 5 hours to dry before the chance of rain. Be sure to soak the moss thoroughly so that the solution can penetrate to the bottom of the moss. In cases of heavy moss growth, wait until the moss has died and lifted free, and then gently brush the dead moss away.
- For Algae, Mold and Mildew:
Spray the area with diluted Wet & Forget Outdoor, allowing 4 to 5 hours before the chance of rain. Green algae, mold and mildew can disappear in a short time, while black algae’s protective pigments cause it to take longer to disappear.
- For Lichen:
Spray the area with diluted Wet & Forget Outdoor at a time that allows 4 to 5 hours of drying time before the chance of rain. Treat lichen when it is not too hot, sunny or windy to prevent the solution from evaporating too quickly. Wait 15 minutes after you spray, and then spray the area a second time. Spraying the area twice allows Wet & Forget Outdoor to penetrate lichen’s multiple layers.
Step 3: Forget It!
Now that you’ve applied Wet & Forget Outdoor, it’s time to sit back, relax, and let Wet & Forget do the work for you! Not only is your work done–in most cases, Wet & Forget will keep your concrete free of ugly growths for a year or more. Re-apply Wet & Forget at the first sign of re-growth to keep the stains from coming back.