Clematis, though the first foot or two needs shade, likes to be in full sun all by itself. Perhaps other members will suggest something that will fulfill your expectations.

You could try Clematis tangutica - its one of the later species ones, starts flowering around July and goes on till early October. Not sure I'd recommend mixing a clematis in with Wisteria though, Wisteria needs a lot of pruning twice a year, and all late flowering clematis need cutting back to about 8 inches from the ground in winter - difficult to separate one from the other over time.

I didn't prune my wisteria in my last garden, just cut off the long tendrils but I can see how it would be difficult to tell them apart from a clematis. Hadn't thought about that, Bamboo, so thank you.

So, if I don't plant a clematis are there any suggestions for a plant that will climb through the ceanothus? Once the flowers have faded it looks very dark against a brown fence. I already have a large flowered pink clematis there but I need something for later in the year.

I have C tangutica Bill McKenzie. It is a good doer and grows freely.[ I often have to give it a hair cut. Mine is just starting to flower and will go on until November . then it has lovely seed heads too.

My wisteria, bought in flower, hasn't done anything since I planted it 3 years ago but this year's growth looks healthy enough. Having said that, at the moment it's not big enough to prune and I have my doubts it will survive. So a clematis such as those both you, Bamboo and Seaburngirl have mentioned should do ok. I was also thinking about Freckles which is lovely.

Thank you both for your help.

any of the cirrhosa types start flowering late October November and can flower all the way through to jan/feb. I have one over a wrought iron gate top.

Many thanks everybody.