Pruning techniques for hydrangeas in the early spring varies by type and is a subject to be covered at a later date.
Summer pruning of hydrangeas however is a very simple task and can be applied to any type of hydrangea and should be done in mid July. Buds have been set and in most cases flowers have developed at this time.
Summer pruning involves removing the green growing shoots that rise above the flowers. Cutting these shoots just below the height of the adjacent flowers improves the appearance and shape of the shrub and increases the number of new shoots that will develop and possibly flower the following year. This technique is called tip pruning and the cut shoots are normally only three to five inches long.