Rhododendron calophytum Rhododendron lutescens Rhododendron barbatum All in bloom on Friday, March 17 in the Asian Garden.
Douglas Justice's March 2017 in the Garden | UBC Botanical Garden blog focuses on the early rhododendrons. Rhododendron lutescens, posted by @Willard, are a week further along now. This plant is pretty much fully open. I'm adding photos to show off the lance-shaped leaves. Here are three plantings of Rhododendron ririei, showing quite different colouring in real life. Also mentioned in the blog is the very beautiful Rhododendron praevernum.
@Willard posted the Rhododendron barbatum. Here are photos showing where it gets its name, and a photo of the bark. In two locations, next to the R. barbatum, are Rhododendron pachytrichum, on the left in the first photo (thank you, @Douglas Justice, for the name), also with hairy petioles, but not impressively bristly like on R. barbatum. I can't resist adding more to Willard's R. caloplyllum photo. Here are two habit photos and their flowers.