Last spring many nurseries here in Maine and elsewhere, including many mailorder sources, were featuring rhododendron Blue Baron. The plants I saw in local nurseries were nearly irresistible with their dense growth and unusual flower color and sold very well judging from the speed with which they left several nurseries. Trouble was, the labels I saw indicated Z4 hardiness - at least a zone and a half too optimistic. Other sellers indicated Z5 - a bit better, but still optimistic.
Blue Baron is a hybrid between Starry Night (Gletschernacht) and Waltham which originated at Weston Nurseries in MA. Weston lists the plant as hardy to Z6 and (quite accurately) says it must have protection from winter sun and wind.
So, curiosity prompts me to ask how many people purchased Blue Baron last year and found it did not survive the winter or suffered severe damage. I'm also curious about how the nurseries which sold them as Z4 plants are dealing with what must be a considerable number of requests for refunds and replacements.
Everybody loses when a rhododendron is given wildly inaccurate hardiness rating. Hard to see how it could have happened.