When should he spent blossoms be trimmed? I did not trim my blossoms after last year's blooming.
Anne Arundel County Maryland
Pruning to control height or to remove old flower heads depends upon the type of hydrangea that you have and whether the hydrangea flowers on the previous or the current year’s growth. See the attached link for pruning tips http://extension.umd.edu/hgic/faqs-shrubs-fallwinter#backyard