Moss and Algae removal that will not kill backyard plants

Asked November 16, 2016, 4:44 PM EST

Howdy, I don't know if you will have a recommendation but the situation is this: I have algae growth that is absolutely out of control on my deck. It actually caused my dog slip and injure herself. I need to get this stuff off my deck. My deck is surrounded by sod and several plants (blueberry bush, rosebushes, and some I have no idea what they are). Is there a product or process that is safe for my poor plants that abut the deck and will get the runoff?

Multnomah County Oregon

1 Response

Here in the northwest, most information is about removing moss and lichens. Algae should respond to a bit less effort. For instance, I’ve found that periodic vigorous sweeping of my sunny concrete patio will remove algae while still wet and, then, I repeat the process as needed through our rainy season.

Some of the methods used against moss will work against the algae. Consider a power washer, making certain to decrease the pressure to avoid damaging the wood. Or apply a commercial solution made especially for use against moss and, then, thoroughly rinsing the deck. Commercial chlorine bleach can be strong smelling and somewhat risky to handle whereas oxygen-bleaches are milder but effective against algae. Good sources of mild but effective products are paint stores and large garden centers.

Still more ideas: ”Methods of moss removal” http://bryophytes.science.oregonstate.edu/page18.htm; “Outdoor cleaning solutions” http://extension.usu.edu/files/publications/factsheet/pub__3096233.pdf ; and “Siding and other exterior surfaces” https://fyi.uwex.edu/house/about-the-house/siding-and-other-exterior-surfaces/

During the cleaning, protect nearby delicate, fragile, and/or treasured garden plants with a light cover.