"rb" wrote:
I'm going to be doing a fair amount of "borders" type work with sprayer
and weed/grass killer.

My question is how much, in general, can you cut the stuff you get at
Lowes, Home Depot, etc (Roundup, ShootOut, Ortho, etc) with water without
losing much effectiveness? I guess it's a way of asking just how
concentrated are most of those products?

You may get away with cutting the water in half or more but the efficacy
might be compromised a tad. Depends on the target.

You have to be careful about bleed too. (into the non-target surrounding
plant material)