Whether or not you get a second flush or a rebloom depends entirely on the type of clematis you are growing. And that's pretty much universal regardless of where one lives. Typically it is only the large flowered hybrids or pruning group 2 clems that offer a rebloom but not all do so. And there are a few somewhat obscure species clems that might have a repeat bloom. Otherwise, the vast majority of clematis bloom once a season.

What cultivars are you growing?

thanks gardengal - I jumped in with gusto when I discovered they would grow in Texas. Somehow, I missed that memo. I purchased 10++ plants to see which I liked best and which would do well in my garden. Most are listed as group 3 or group 2 or3. Planted in February they all took off and bloomed in late spring even as baby plants and all except one have been blooming this fall. Some bloomed sporadically this summer. I do not have those mass of blooms sent from my friend in Virginia and I would like to increase blooms if I can. The pictures were from Sept and they a few more blooms now with our cooler Oct weather.

I bought the ones described as large flowers that were available at Brushwood and Silver Star. Got a great one called Blue Nights from Proven Winners that bloomed all summer but has shut down this fall. Baby plant so one or two blooms at a time were a gift. By bloom I mean like my pictures which is no comparison to pictures I have seen from elsewhere.

Increased flowering will come from good care and time. If they were mine, I would prune them back hard this winter regardless of pruning group (typically recommended for all 1st year clems) and give them a good spring dose of organic tomato or rose fertilizer - something that has alfalfa meal in it. Alfalfa contains a natural plant growth hormone that encourages basal stemming and the more stems the vine has, the more flowers it will produce. It also makes the vine less vulnerable to diseases and mechanical damage.

I have a 5 year old Jackman Clem. The first year it bloomed a bit but only reached 4-5 feet or so. It's a type 3, and I cut it to about 12 inches from the ground each Feb. The second year it grew a bit more. But by the third year i started getting flushes like this from mid April to May. The top of the trellis is 9 feet, which this clem reaches by the end of March.

The rest of the summer it spits out a few blooms here and there but not nearly as much as this. I bought it to cover an electrical box, which it does nicely.