Seeds from Dichroa febrifuga Blue Evergreen Hydrangea. A 3 to 7 foot tall by 5 foot wide, half-hardy evergreen shrub from the Hydrangea family. The 4 to 8 inch long dark green leaves resemble the foliage of Hydrangea with prominent veins and small serrations. The terminal end of the branches hold clusters of hydrangea-like flowers with white buds opening to bright blue flowers in spring and summer that are followed by metallic blue berries. As with the blue forms of Hydrangea the shade of blue of the flower is determined by soil pH or more aluminum in soil and more acids in soils produce bluer flowers. Zones 8-10.