Eliminate Backyard Deck Moss

Get tips on how to eliminate moss on your backyard deck. Find out what may be causing the moss to grow on your deck and what to do to get rid of it.

LESLIE: E.T. in Tennessee has a question about a deck. What can we do for you?

E.T.: About 10 years ago, when I moved to Tennessee, I bought new construction here. Matter of fact, I bought the first house in a new subdivision. And it had a deck on it and then …

TOM: OK.

E.T.: … about four or five years ago we had a roof put on the deck and then last year we turned that into a sun room and built another deck.

TOM: (chuckling) OK.

E.T.: And when I built the other deck, I had them to put plastic down over the ground so the weeds wouldn’t come up through it and now I’m starting to experience some light green moss or mold on the one side of the deck there and I thought maybe the plastic being under it might accumulate moisture and cause that. And if so, I was wondering what I could do to alleviate that problem.

TOM: OK. Is it a shady backyard?

E.T.: It’s shady on the side that that’s affecting, yes.

TOM: Mm-hmm, yeah. Well, what happens is you have a humid area and you don’t have a lot of sunlight so you get a lot of moss that’s going to grow. And you know the only solution here is regular maintenance, regular cleaning. There’s a …

LESLIE: Yeah, there’s no magic solution that’s going to make it go away forever.

TOM: (overlapping voices) There’s no magic here, right.

LESLIE: What you can do is trim back whatever trees that you can to help get more sunlight to this area because that will be a natural preventative.

TOM: But of course, you don’t want to do that because then you’re going to have a hot deck.

E.T.: Well, that particular side of it is next to the house so there’s no way to remedy that.

TOM: (overlapping voices) I see.

E.T.: So what I’ve been doing is just pressure-washing it with bleach and then putting the sealer back on it, you know.

TOM: There’s a product called JOMAX – J-O-M-A-X – that is a good product for controlling this issue. It’s made by Zinsser; available at home centers, hardware stores, et cetera. You mix it up with water and bleach and it does a really good job of killing what’s there.

It’s important that, you know, when you apply this type of product, or even bleach, that you let it sit there for enough time to do its work and then wash it off with a pressure washer; you can’t do it all in one fell swoop.