This white rhododendron is in bloom now in the Ted and Mary Greig Rhododendron Garden in Stanley Park, near Ceperley Meadow, if I remember correctly. I thought the prominent yellow stigmas were unusual - is that true? I don't see it pictured on my Parks Board brochures.
More interesting feature for id is the deep red throat. There are 1000's of Rhodos species and hybrids. Need a real expert to see size of flower, shape, colour, leaf shape, size indumentum etc etc. So this is just a suggestion...Rhododendron falconeri ssp falconeri. ......Leaves broadly elliptic to obovate, up to 14" long, rust to brown indumentum. http://www.hirsutum.info/rhododendron/species/picture.php?id=420&url=420_4 http://www.rhododendron.org/descriptionS_new.asp?ID=255
The leaves look smoother than on the R. falconeri in Silver surfer's link. I posted R. calophytum from UBCBG three days ago and didn't recognize that I'd just seen this plant. At UBC, the drooping leaves under the flowers caught my attention; here it was the exceedingly long styles, with the stigmas about one cm. outside the cups.
R. falconeri etc. are from a different part of the genus, perhaps not in bloom yet. Might not persist on Greig site either, except for R. rex. And these are all much hairier than this plant, which has characters of R. calophytum. As the corollas may be a bit broad for it and the leaves shown don't have the typical long, narrow shape it is perhaps one of its hybrids, either a named cultivar or an open-pollinated hybrid seedling planted there as an example of the pure species by mistake.
