Rhododendron hybrida ( Minstrel Glenn Dale Azalea )
unfold , vigorous , evergreen azalea developed mainly for dusty hardiness along the mid - Atlantic State . undivided , funnel shape - shape , rich crimson flowers with burgundy splotch , 3 column inch broad . Flowers are borne in showy trusses of 3 to 5 per bunch . efflorescence time is late April in warmer areas and as late as early June in cooler climates . Plant as you would any of the other azaleas : eminent and in well - drained , acid soil , fertile with organic matter ....