On Sun, 17 Feb 2008 11:16:10 -0800 (PST), "
wrote:

I admit I'm lazy. My concrete patio is only a couple of years old.
I've decided to apply concrete sealer to protect and extends its
life. It doesn't have any grease stains, dirt or mildew. Do I still
need to use a concrete cleaner before applying the sealer?
Thank you


It is best to follow the manufacturer's suggestion on cleaning. A
power spray washer is the standard for cleaning concrete, although I
have never "cleaned mine," just kept it swept. The fall leaves
sometimes stain the concrete, but the sun eventually bleaches out the
stains.