Hi Warren,

San Francisco has near perfect climate for these plants, so you are really lucky in that respect.

If there's any way you can do it, I would highly recommend that you go to the sale at Strybing this weekend, preferably on the member's day (Friday evening). If you can't make it and you know someone who is going, you might ask that they pick up a couple plants for you ($15-$20 each?). There you will also be able to ask questions of the experts--probably Carlos and Dave (although I don't know for sure that either will be there, or what days/times).

At the member's day of the sale they will have the best selection. I remember last year they had plenty of P. parritae, and I believe the 'Mission Dolores' went quickly. I have no idea what they plan to sell this year, but chances are good they will have all 4 of those plants. Another good source for the plants is Grassy Knoll Exotics, but her plants will be smaller as they are sent through the mail. I recommend Grassy Knoll highly, also Annie's Annuals, but since you are already in SF you might as well go to Strybing and get a big plant. I think Strybing (and UCBG) are the best bets for finding P. parritae. And the member's sale is the most likely time to find them.

As far as your setup, that sounds reasonable. You will need something for them to climb. P. x exoniensis blooms easily in small (1 gallon) pots, P. 'Mission Dolores' in 5 gallons (and maybe a lot smaller). I don't know about P. antioquiensis and especially P. parritae blooming in pots--perhaps someone else knows. It sounds like yours are much bigger than 10 gallons (?) so maybe it's not an issue. The people at Strybing may be able to help you there. I have seen 'Mission Dolores' growing over a fairly low arched structure at a private garden in the city, although you may be able to get more info at the sale.

Another question is sunlight and I don't know how much these guys take in the city (and it may depend if you are in a sunny area). Again Dave or Carlos should know. P. x exoniensis I think can take full sun in the city, and probably P. antioquiensis the least.

I would guess that the easiest and quickest to bloom of those 4 is P. x exoniensis. P. antioquiensis and P. parritae seem to have a reputation of taking several years to bloom (in SF). Is flowers hanging down truly a problem? They can be pushed out of the way if necessary. P. x exoniensis would be the least of a "problem" in this way.

All of these are fast growing vines: >1 inch/day in the summer. P. parritae has a reputation for sometimes being slow to get established. They can always be cut back, although you don't want to get rid of the long vines and all the new growth, as this is where the flowers come from.

Other species to consider: P. membranacea has interesting leaves and nice, but totally unique flowers. P. loefgrenii is an easy plant with Seuss-esque flowers on mid-length peduncles. P. gritensis will be hard to find and can be a bit ugly as a plant but the flowers are amazing. There are many others, all reasons to go to the sale...

Here is a link that might be useful: Strybing plant sales