Begonia boliviensis ‘Santa Cruz’ is one of those modern cultivars that I am typically not so keen on. It grows vigorously with abundant red bloom. ‘San Francisco’ is similar but with abundant pink bloom. ‘Santa Barbara’ is similarly similar but with abundant white bloom. All perform splendidly, like so many formerly modern cultivars that were trendy before them. I am not so keen on them merely because they are both modern and trendy. Their names do not help either. My colleague purchased ‘Santa Cruz’ from a nursery in Santa Cruz. It now lives here in Mount Hermon, which is a few miles away from Santa Cruz, but still in Santa Cruz County. I suspect that it is more popular locally because of its name. For the same reason, I suspect that ‘Santa Barbara’ is more popular in Santa Barbara, and ‘San Francisco’ is more popular in San Francisco. I also suspect that I would be less resistant to these modern cultivars if they had more appealing names, such as ‘Los Gatos’, ‘San Jose’ or ‘Palo Alto’. Perhaps the names are for the counties rather than the cities within the counties. All three of my recommendations are within Santa Clara County.
Tony Tomeo 
Hmm, I seem to have purchased the white one this year. I do really like these begonias and they’re rarely, if ever, available by us. I don’t recall it having a name. I will have to hunt down the tag and let you know.
By us, of course, they’re sold as house plants or “trending tropicals ” for containers. Mine is currently outside but I hope to bring it in if I have room.
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If it is Begonia boliviensis, with flowers that look just like these but white with yellow stamens, it could be ‘Santa Barbara’. It got my attention because it is white, but with the yellow stamens, it is not such a plain and simple white. Besides, I am not so keen on modern cultivars.
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The leaves look just like that. I haven’t seen too many flowers but they are white with yellow stamens. Mine seems to be much less upright and more sprawling but it’s in full shade so that probably has something to do with it. And I know that this is the least “horticultural” answer you have heard in a long time but I am nowhere near my plant. I just realized I don’t even have a photo for reference. How lame!
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Unless necessary, I do not take pictures of my vegetation either. I am a horticulturist, not a photographer. Begonia boliviensis is actually a sprawler, the specimen that I got a picture of is atypically upright. It will likely fall over from its own weight soon, and then grow from sideshoots.
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Well, mystery solved. It is indeed a begonia boliviensis–but it’s a Proven Winners cultivar called Bossa Nova White. Who knew Proven Winners had gotten into these plants? So there we are. It’s doing great and surviving all our heat and rain.
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‘Bossa Nova White’ might be whiter than ‘Santa Barbara’ if ‘Santa Barbara’ has more prominent stamens, or the two could be the same. I doubt that Proven Winners would use two names for one of their cultivars.
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When I looked it up, (because as I always tell people, don’t rely on those tags, necessarily) it said continuous bloomer and drought tolerance were 2 of its attributes. Yeah, I would expect that from a begonia. What I did not expect is survival in our soupy conditions this summer–the fern next to it is just loving things! And yes, it said pure white, if that’s helpful.
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Drought tolerant?! I do not trust that. Are the stamens not prominently yellow?
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This is interesting. We clearly understand “drought tolerance ” as very different things, probably because of our experiences. You have much more experience and therefore understand it better than I do. I read that to mean that they withstand dryness better than the typical begonia–but not that they were in any way a xeric type plant.
And I still have no true way to tell because I don’t think that I have given that plant water more than once this summer–nature is doing my watering for me. Even today we are getting the remnants of the latest tropical storm. That’s just a bit too much watering for my liking!
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‘Xeric’ is actually a better term that I had not considered. ‘Drought tolerant’ can be annoying to those of us who live and work with chaparral or desert climates because those who are unfamiliar with such climates refer to our normal weather as ‘drought’. One can actually read about how ‘every year is a drought in California’. If it happens every year, it is not a drought, it is normal climate!
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