I never have. I had the same experience as you; no matter how early I started plants I didn't get flowers until late summer. So I thought it needed warm temperatures. But then the darn thing kept blooming until November in central Ohio!

I've heard that cobaea is naturally pollinated by bats, but that the bats we have in North America simply don't do that. Found a few articles that reference that, this from a UCLA publication:

Bat pollination is especially important in certain families, such as Old and New World Bombacaceae, including the baobab, kapok, and floss-silk tree species. Classical examples of bat flowers occur in the Bignoniaceae, including the sausage trees cultivated on the UCLA campus, and calabash, among others. Cobaea scandens, a cultivated vine of the phlox family (Polemoniaceae), has flagelliflory and is bat pollinated in western South America.

Although in Westwood we have some bat-adapted flowers, and these plants form fruits, we have not determined yet whether bats are responsible for fruit formation on campus. This sounds like a good nighttime homework assignment for a UCLA undergraduate student, one not afraid of bats and vampires.

And from the Kemper Center for Home Gardening:
Native to Mexico and tropical South America, cup and saucer vine is a vigorous, rapid-growing, tendril-climbing vine that typically grows to 30-40 in its native habitat. When grown as an annual, it can grow 10-20Â in a single season. The descriptive common name is in reference to its bell-shaped flowers (cups), each of which is subtended by a saucer-like green calyx. Flowers last about 4 days, emerging green but maturing to purple. Flowers have a musky fragrance. Blooms late summer into fall. Pinnate leaves have four leaflets. Also commonly called cathedral bells. Flowers are reportedly pollinated by bats.

And this from the Encyclopedia Britannica:
Certain highly specialized tropical bats, particularly Macroglossus and Glossophaga, also obtain most or all of their food from flowers. The Macroglossus (big-tongued) species of southern Asia and the Pacific are small bats with sharp snouts and long, extensible tongues, which carry special projections (papillae) and sometimes a brushlike tip for picking up a sticky mixture of nectar and pollen. The plants involved have, in the process of evolution, responded to the bats by producing large (sometimes huge) amounts of these foods. One balsa-tree flower, for example, may contain a full 10 grams (0.3 ounce) of nectar, and one flower from a baobab tree has about 2,000 pollen-producing stamens. Some bat flowers also provide succulent petals or special food bodies to their visitors. Characteristics of the flowers themselves include drab colour, large size, sturdiness, bell-shape with wide mouth and, frequently, a powerful rancid or urinelike smell. The giant saguaro cactus and the century plant (Agave) are pollinated by bats, although not exclusively, and cup-and-saucer vine (Cobaea scandens) is the direct descendant of a bat-pollinated American plant. Calabash, candle tree, and areca palm also have bat-pollinated flowers.

Somehow I don't think we can replicate this with a soda straw and long fingernails!

I am thrilled with the bat info!
I will try hand-pollinating. Unfortunately, as far into November as these Mexican beauties have gone, we had a frost, and they are droopy. Not the whole plant though; however, I do believe it is too late to expect a fruit to mature. I'll put it on next year's TO_DO list!
Robin

My cobaea vine reached about 30 feet this year. I started it indoors in March, it didn't flower until late July or maybe early august, and then it just died before it did anything. I was horrendously dissapointed bacause I didn't get any seeds, can't find any anywhere, and wanted desperately to grow it again next year. I hope you have better luck!!!

I never have luck with this one. My first attempt, I bought a pack and either they never germinated or strangled on the seed coats, I can't remember which was which.
Last year, the local arboretum had a fantastic display of them on a chainlink fence. There were several plants all flowering. They did produce large fruit but it was always still green everytime I went back. Still I took my son for classes so I checked every week. But they took the display down before anything ripened. It is very possible that others took anything that ripened but otherwise by that example, it takes a long while for the fruit to mature, longer than my season.
Then last year I found a plant at a nursery but my husband weed wacked it.
It is a beautiful vine and the flowers are substantial. I won't give up on this one.

Found these today on a vine in southern RI! It's the first time I've seen these on any cup and saucer vine! So exciting but sadly not sure what the secret is. The place it's growing is a 300+ acre estate. I see more diversity in pollinators here than anywhere else in the area so I'm guessing that has played a big role.

I have grown this plant for the first time this summer. It grew well, flowered early autumn and produced several pods. I collected the pods (still green) after the first frost. I’m in the Pacific Northwest Canada. Today I peeled the skin off one pod and it is lined with seeds. I just don’t know what to do with them now. Do I dry them out and save them or should I be letting them spend more time in the pods? Perhaps until they dry out? Anyone have any thoughts on this?

I collected the pods and took the seeds out of mine last year in the autumn and dried them took them out the pods and dried them out they grew as well as some I bought and I now have a superb plant with 5 pods this year. Pretty good given the poor summer.

my purple one has pods but none on the white its now november and im wondering if i cut the pods off snd dry them inside or leave them on the vine to dry might not happen before frost i have a soutce for seeds so not a big deal but would like to collect my own seeds