I had a patio installed in 2007 with Lampus Heritage interlocking pavers. It still looks good. There's no chalkiness on the surface. The color may be a little less intense than when it was when intalled, but I like that. This spring, for the first time, there are some weeds coming up at the joints. Two questions:

-- Should I put a sealer on the pavers this spring or wait until it looks like it needs it, then clean and seal? I don't know whether you need to seal to maintain the integrity of the paver (and therefore need to seal regardless of how it looks) or whether the sealer is to solve appearance prolems caused by stains or age, in which case I don't seem to need it yet.

-- Should I brush polymeric sand into the joints to reduce the weed prolem? Or should I just sprinkle salt into the joints (does this really work with weeds?) or use Roundup (might it stain the pavers?).

My contractor has flown the coop so any advice would be welcome.