Bigleaf hydrangea Hydrangea 'Blue Boogie Woogie'® Blue - Hardy plantLook at the colour! The 'Blue Boogie Woogie' (Hydrangea macrophylla) catches your eye in the garden. The bush has blue, almost purple, flowers you can enjoy for months. The flowers bloom from summer to autumn. Pruning is not necessary, unless the bush becomes too large. Plant the hydrangea in partial shade. The soil should be kept damp. Give it extra water during dry periods.