Sambucus nigra ssp. caerulea
 
Tall deciduous shrub (though nearly evergreen in mild climates) growing in a variety of conditions and reaching typically from 15 to 20 feet at maturity, often taking a broad, tree form. The blue elderberry is  more tolerant of dry and hot conditions, though it likes regular moisture.  In the wild it is most commonly found along streams and waterways.
 
Yellow-white flowers are followed by blue berries that are visible from a long distance and add a distinct beauty. Berries are also often used in cooking and preserves, but must be cooked to avoid toxicity.  Important food source for birds.
 
Size: 15-20' T
Sun: Prefers full sun; tolerates some shade
Water:  average to moist soil
Blooms: May-Jul