Erase Black Streaks on your Asphalt Shingles with Wet & Forget Outdoor

Erase Black Streaks on your Asphalt Shingles with Wet & Forget Outdoor

You spend a bundle on quality asphalt shingles, only to see black streaks appear out of nowhere. Now your roof looks like someone rubbed it with soot, and your big investment is an eyesore. Don’t take it lying down!

Read on to find out what causes those ugly stains, and how Wet & Forget Hose End erases them with no scrubbing.

What Causes Black Streaks on your Roof?

cleaner for black streaks on roof

Those black streaks or splotches you see on your shingles are most likely black algae.

Black algae is a simple growth that can develop on just about any outdoor surface where there is sufficient moisture. And, unlike green algae, which prefers to grow in partial shade, black algae can grow even in the sunniest spots, such as your rooftop or on concrete surfaces such as sidewalks or driveways.

That’s because black algae are encased in a pigmented protective capsule that gives it its black or charcoal gray color, and which also protects it from the sun’s harsh rays. Black algae’s protective capsule also makes it difficult to clean.

Why Bleach or Pressure Washing Aren’t the Answer

Some homeowners turn to bleach or pressure washing to clean roof stains, but they aren’t the best option for cleaning black algae on asphalt shingles. Bleach is a caustic chemical that runs the risk of corroding your home’s downspouts, damaging your lawn with caustic runoff, and even causing some shingles to prematurely shed their protective granules.

Using bleach on black algae also requires brisk scrubbing and rinsing, which makes it a pretty work-intensive job and can also increase the wear and tear on your roof.

If you pressure wash your roof, the force from the water can cause your shingles to shed their protective granules, tear shingles loose from the roof’s membrane, knock your downspouts out of whack, and force water into spaces where it doesn’t belong.

After all of that hassle, these methods fail to reach the root of the stain and even leave a food source behind, which can cause growths to come back quicker and thicker. This means you will be back on your roof with the bleach and scrub brush or pressure washer, again and again, stuck in an endless cycle of cleaning and re-cleaning.

Erase Black Streaks with Wet & Forget

brick cleaner

Wet & Forget Outdoor breaks you out of the cleaning cycle. Wet & Forget Outdoor eliminates black algae on your roof with no scrubbing, rinsing or pressure washing needed.

Just spray and leave! Wet & Forget Outdoor works with the wind and rain over time to completely wipe out black algae and keep it away for a year or more in most cases.

Wet & Forget’s gentle, non-caustic formula is safe for all types of shingles, and it won’t corrode your downspouts or harm your lawn with runoff.

Because it works with the rain, Wet & Forget Hose End’s cleaning power reaches the nooks and crannies of textured surfaces such as asphalt shingles much better than your scrub brush can for a more thorough clean, without the extra wear and tear that all that scrubbing puts on your shingles.

What other Stains Does Wet & Forget Hose End Remove?

best roof moss cleaner

Black algae is a big problem on roofs, but it isn’t the only problem. For example, moss is also a problem on many roofs, and it can cause serious damage or even put you in danger of losing your homeowner’s insurance. Here are all of the growths that Wet & Forget Hose End eliminates:

Wet & Forget Hose End’s gentle formula is safe to use on just about any outdoor surface, including:

How to Apply Wet & Forget Hose End

Eliminating black algae with Wet & Forget Hose End couldn’t be easier. Simply:

  1. Attach the Wet & Forget Hose End product to your garden hose and connect the Jet Setting tip. Turn the water spigot on, then turn the hose end dial to “WATER” and rinse down nearby landscaping. Next, turn the dial to “ON”
  2. Spray the affected area with the diluted Wet & Forget Outdoor at a time that allows at least 4 to 5 hours’ drying time before the threat of rain, when the temperature will stay above 55 degrees Fahrenheit. Turn the dial to “WATER” and rinse down the landscaping once more.
  3. Walk away, and let Wet & Forget Outdoor do the work for you!
  4. Re-treat once a year, or at the first sign of re-growth.

Be very careful walking on your roof; surfaces may be slippery. If you don’t feel safe on your roof, call a professional.

Try Wet & Forget Outdoor today and love your roof again! Stop by our website to learn more about our easy solutions to everyday problems, so you can spend less time cleaning and more time enjoying life!


  1. Donna

    Are these Directions correct on this page for cleaning black algae with wet and forget? The how to use instructions aboVe say to mix one Part water with five parts wet and forget. Does it have to be that much of a stronger solution for black algae than the one part wet and forget to five parts water for green mold?

    1. Wet And Forget

      Hi Donna,
      Yes, Wet & Forget should be mixed 1 part Wet & Forget to 5 parts water to remove moss, mold, mildew, and green algae stains. You don’t want to over dilute Wet & Forget with water as this will leave you with undesirable results.