Answer: Nova Zembla is the first deep red that came to my mind, then Lord Roberts or possibly Henry's Red or even Skookumchuck (these widely popular cultivars are in the Monrovia listings), but there are so many different red rhododendrons there is no way I could hope to tell you what it is by guessing.
You could also try to identify it based on photos using the search feature at the American Rhododendron Society web site. (Perhaps they could help you identify it from a photo?)
You might stop and ask if you see one growing, perhaps the owner will still know the name. Otherwise you could try checking catalogs from specialty growers such as those listed by the Rhododendron Society at
I'm sorry I can't tell you exactly what it is but I hope this helps you get started in researching it.
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