this pretty shrub/tree was flowering next to what appears to be Rhododendron cinnabarinum. Photographed in mid-May.
Philadelphus delavayi or P. delavayi var. calvescens have purple calyces like that and are in the same plots in the garden as Rhododendron cinnabarinum. For some reason I seem to have on my computer a photo of P. delavayi by Daniel Mosquin with leaves that look slightly different and totally white buds, as Sundrop mentioned.
Yes, I have seen that photo and the leaves and white buds prevented me from identifying the one on OP's pictures as P. delavayi. May be a different variety than on Daniel's picture?
Where is that photo from? Maybe repost it. I really only remember this one: Philadelphus delavayi - Botany Photo of the Day
That's the photo. I was going to look to see if that's where the photo was from, but I didn't realize we had the PBotD archive postings back, didn't think I'd be able to find it.
Well, we have several as-yet unidentified Philadelphus in the Asian Garden from wild collections. Maybe if I had a slightly more accurate location, I could go have a look for a label.
Thank you all for your interest! As for location, it may have been near the Farrer/Ludlow trail junction but I'm not so certain of this. What I can say with certainty is that I had photographed a Cercis glabra 1 minute earlier and then, heading back to the main entrance, a Decaisnea fargesii (overhanging the path) about 3 minutes later. The plant in question, and the R. cinnabarinum made somewhat of a tall thicket on the north side of a trail. I couldn't find a label.
Fortunately for trying to figure this out, we only have one Cercis glabra plant, so that makes it easy to narrow down location. In a small radius around that Cercis, there are only plants identified as Philadelphus delavayi. A little bit further away is a Philadelphus brachybotrys.
I am sure I have found THE plant. It's in area 3ADA, on the north side of Lower Asian Way just before Farrer, directly across from the Sorbus caloneura. The only Philadelphus that is supposed to be there is P. delavayi. It does have some pink edges on the buds. It's very tall - almost everything green in the second photo belongs to it, except for the Rhododendron cinnabarinum. I also found what I think is its label, but I wasn't up to going in there to read it. I've circled the label in this photo. If anyone at the garden is up to reading the label, could you also read the label for the rhododendron immediately to the left (not the R. cinnabarinum, the one on the other side)? Here's a photo showing where the label is. Nothing that is supposed to be in that bed should have leaves like these, and I'm looking for R. orbiculare, which looks similar to this, but I'm not certain, would prefer to know if I catch in with open flowers, since it was mentioned in the April in the Garden posting. Again, the location of the label is circled. [Edited]I found another photo of the label in the centre of the photo, not readable. I think this has to be the same tree.
Here are some photos of the open flowers. These Philadelphus delavayi from the thicket nearer the Decaisnea have no pink. And these from the group just west of Farrer have pink on the buds, and occasionally but not often a tinge of pink on the open petals. The question is whether that bit of pink would be enough to give the plants a different name. Since these are species plants, maybe some variations could be expected? I don't know that I would recognize Philadelphus brachybotrys - the name should refer to short inflorescences; no photos from Google show any pink on the buds, and it seems to have hairy calyces, so not these. I was able to capture the name on the tag for the Rhododendron decorum.
I've taken photos of the labels on this plant... but camera at home today. It did say P. delavayi on the label, but also had a wild-collected number. I'll try to remember to look at this tonight.
Right. 29402/0-0010-1992 or 1992-218, Philadelphus delavayi determined by B Zhuang in 2010. Originally received as Philadelphus sp. aff. calvescens CLD.0768, collected from Yulong Shan in Yunnan at 3150m.
Or, an alternative identification from a collection elsewhere: Philadelphus purpurascens Hydrangeaceae CLD768 China Yunnan, W: Lijiang Pref.: Lijiang Naxi Aut. Co. Royal Botanic Garden Edinburgh 19910648 Guess we will have to reverify.
If you get a new name, here is a beautiful photo of yours (Daniel's) that also has the pink markings, different accession (10 years earlier): Asian Garden: - Philadelphus purpurascens [Edited]I was thinking this might also need renaming, but realize that the issue would be whether the plant that is the subject of this thread would get the name P. purpurascens.
Here are photos of developing fruits from what I'm assuming is the individual in question and the Philadelphus delavayi where the descriptive sign is.