>>7972663Kalmia Latifolia.
These are native in the Middle Atlantic states of the USA. They are to be found in woodland shade, preferably in peaty, somewhat acidic soil. They like the north (shadiest) side of hills under a forest canopy. They bloom mid to late May. The flowers are real eye-catchers, but the scent is very faint.
In the wild, form & habit are irregular, leggy. Older specimens can be quite open. Blooms on wild plants tend to be white, sometimes light pink. Foliage is evergreen.
These can take sub-zero winter low temperatures and still look great in spring.