When is the best time to prune a Nikko Blue Hydrangea? Mine had no blooms at all last year.
The best time to prune Nikko Blue Hydrangea is after the flowers are ending in Sept or Oct . Nikko Blues bloom on old wood unlike many other hydrangeas. Cut off the blooms just below the bloom. Look down the stem and find a new set of buds starting up. Make a straight cut half an inch above the bud.Stand back and check the shape of the hydrangea periodically and adjust where you are cutting to suit the site and shape of plant you want.
If your Nikko Blue is in a cold or windy location, you might want to only cut off the flowers in the fall and then prune just above the buds in the spring after you see how much winter kill there is. If rain is forecasted for the next three days, it’s advised that you not prune until after then as water borne bacteria could get in to the plant.