Not necessarily.

Leaveswave, I don't know where you live, but my Type II pruning groups bloom in late May if I haven't cut them all the way back in the spring (which I do only to young ones so they will build up roots and stems - in that case, they will bloom later). My Type III's (Viticellas, Texensis, and Jackmaniis, etc) usually bloom starting in mid to late June. Every year is different, though, as is every area. If you are wondering what clematis you have, post a picture and maybe someone can ID it, and then you would have your answer.
Judith

Pruning group 2's will have two flushes of blooms..once in early spring and again in late Summer/early Fall..they will have blooms all over the vines..old vines and some on the new vines..whereas Pruning group 3's bloom after the 2's and ONLY on new vines produced during the growing season..that is the great thing about pruning group 3's..if you only see blooms on the new vines then you know you haven't hard pruned it like it needs...Jeanne

Yes.....roughly :-) When a specific clematis blooms does tend to indicate a pruning group (that's often one of the ways suggested to determine how to prune an unidentified vine) but as BorS suggests, the line sometimes become blurred.

In general, early blooming vines (before May) bloom on old growth and require minimal to no pruning. If pruning is desired, it is best do so as soon as possible after flowering so as to allow sufficient time for flowering growth to develop for the next season. Midseason bloomers -those that flower anywhere from early May into late June/early July (weather determined) - are most often considered to be pruning group II's. These bloom primarily on old growth and should be pruned lightly once established. Not all group II's will offer a later rebloom; in fact, this group is sometimes subdivided into two groups to indicate those that rebloom and may require an additional light pruning after first bloom flush and those that do not. Late season bloomers - late June and after - are generally pruning group III's and bloom on new growth only and tend to respond best to hard pruning.

In mild winter climates and those where the seasons tend to blend and are less distinct - like the Pacific Northwest - you do encounter some overlaps, but in general bloom time does correlate to pruning guidelines. And it is always a good idea to hard prune any new vine regardless of flowering time or pruning group for at least the first one or two growing seasons to aid in establishment and to encourage multiple stemming from the root crown.

You know it's funny. I have a Franziska Maria that is a "pruning group 2" supposedly. I never saw her bloom at all in the last two years even with early spring pruning. So, this year, I decided to not prune her at all until after blooming. I got blooms then! Gorgeous ones! Not many but nice anyways. Sometimes I wonder about whether she's really a group 2 or maybe even a 1. She's now 3 years old so still a little young. Maybe next year more flowers?
I did prune her after blooming this time, to get her to produce more stems from the ground and have been using alfalfa meal and tea and Mills Magic Mix.

The vast majority of large flowered hybrids are included in pruning group II with a significantly smaller portion included in pruning group III. None are considered in pruning group I, as these are almost always species clematis, typically atragene types but also any of the evergreen species as well.