I have had very good luck with growing Clematis vines with roses. The texensis and viticella types do better in our Texas climate, IMO. I avoid evergreen or vigorous vines in combination with roses, as they overpower the rose and diminish air movement. These clematis types can be pruned hard each year, greatly reducing the risk of "takeover" of the arbor. I have been successful in growing sweet pea vines with roses as they are an annual and are easily pulled up when our temps start climbing.
Molly

Tangerine Crossvine.

Here is a link that might be useful:

Thanks for the input. I looked at moonflower and morning glory seeds this morning in my local feed store but didn't see any clematis seeds. The tangerine crossover is pretty but that picture makes it look like it could take over.

You won't find the clematis seeds, but you can buy a nice plant at a reputable nursery. The tangerine crossvine is, indeed, a very vigorous vine and will choke the roses out, particularly in southeast Texas where we have a long growing season.
Molly

Quite a few threads on the Weeds forum about getting rid of morning glory. It is said that the seeds can remain dormant for up to 20 years before they strike.

The clematis Texensis/hybrids can be hard to find locally, but even the old 'Jackmanii' varieties sold as dormant roots in the big-box store bulb areas do surprisingly well in our north Texas heat and clay.

Yes, Jackmanii clematis is readily avalable and is a very good performer. Clematis are also long-lived plants so they are a very worthwhile investment IMO.
Molly

Thanks everyone. If I can't find clematis soon I will opt for the morning glories and moon flower mixed together.

I grow various annuals (thunbergia alata, eccremocarpus scaber, mina lobata, nasturtiums, including various tuberous tropolaeums), rhodochiton atrosanguineus is a dainty late flowering perennial climber, lapageria rosea, mandevillas). For a rampageous, but rather glorious annual, have a look at cobaens scandens - the white is more mannerly than the purple. Also, a couple of the solanums might do well (solanum wenlandii or the variagated solanum laxum), labalab, petrea volubilis (I cannot manage this - too chilly in the UK).......which brings me to explaining why I am lurking on a forum about which I know absolutely nothing. Hanging around the perennial forum, there have been thrilling (to me) discussions about plants I have never heard of.....plants I badly want to know about, sow and grow - fantastic plants which are really impossible to find in the UK (many fabulous penstemons, for example )........

Susie, I am so glad you mentioned all of those nice annuals. I have grown the mina lobata and thunbergia alata from seed and I have been very pleased with both of them.
I also have two different solanum vines, but I find that with our long, warm, growing season they are a little too vigorous to grow alongside roses. If I can get my hands on a cobea scandens (cup and saucer vine), I will be delighted to add it to my garden.
Glad you checked in on us Texans!!!
Molly