Updated February 2020
Why Did my Deck Stain Turn Black?
We appreciate it when people write in and ask for advice when something goes wrong during their deck staining projects. Today we talk about what causes your deck stain to turn black after a year or two and what to do to get rid of the problem. We appreciate your input, so feel free to leave a comment below with pictures of your deck stain projects.
Why Did Your Deck Stain Turn Black?
Many things can happen to a deck stain when it is not applied or maintained properly. The biggest reason for a deck stain turning black is mildew. All wood surfaces need to be cleaned correctly prior to staining. The use of a quality wood cleaner and pressure washer or scrub brush is necessary to remove all the contaminants like dirt, grime, mold, mildew, and graying.
When contaminants are left in the wood pores and stain is applied a whole host of problems can occur. Mildew can begin to grow underneath the deck stain, which causes discoloring. This can also lead to rot and decay because if there is mildew there is also moisture present.