How do I trim to make them bloom more?

In our hydrangea planting and care guide, we have a section on pruning. First, it’s important to pick a spot in the garden where your hydrangea can mature to its full size. That will help lessen the needed for additional pruning to force it into a small space. Remember that Endless Summer Hydrangeas flower on both old and new wood. If some winter clean up is needed, prune in early spring. Then deadhead during the summer to help the hydrangea grow new flowers.