The sooner the better!!! I know a lot of us like to grow our puppy's hair out, but that doesn't mean they shouldn't go to the groomer. You can bring your pup in for a tiny trim up around the eyes and sanitary area. Or even for a bath! This will help them get used to going to the groomer and will let you get a feel for what groomer you like. The later you wait, the less likely your pup will accept the grooming process. This can make him/her difficult to groom and it will be difficult for him/her because she's stressed
I say as long as they have 2 rounds of vaccines with Bordatella included, then bring em on in!! Be sure your groomer understands that it is Fluffy's first cut. When I have first timers I spend a lot of extra time on them, taking it slow and talking to the pup so they feel comfy. Good luck!