Rhododendron hybrida ( Gawain Glenn Dale Azalea )
Upright to widely spreading , dense , semi - evergreen azalea developed primarily for cold boldness along the mid - Atlantic states . Single , funnel shape - work , lilac - purple flowers with grim purple blotches , 2 to 2 1/2 inch spacious . bloom are borne in showy trusses of 1 to 4 per cluster . blossom time is belated April in warmer areas and as belatedly as early June in cool climates ....