How can I get my two hydrangeas to bloom?
It depends on the variety of hydrangea. Some hydrangeas put out new growth in the summer and flower afterwards. They should be pruned, cutting away only dead wood, either in the fall or very early spring. Other hydrangeas will bloom on either “old” or “new wood.” This means if the buds are killed during the winter, they will produce new buds in the spring which will produce blooms. In general, prune only dead branches, and do not prune to “shape” the bush. Climate is another factor that can affect blooms. Some hydrangeas, such as oakleaf hydrangea, perform better in warmer areas, such as USDA Hardiness Zone 8, and they may have difficulty flowering in colder climates, such as USDA Hardiness Zone 4. An early spring or late fall frost in Zone 4 might be enough to kill any developing flower buds. You may want to contact a local nursery or your local county extension agent to find out more about your variety.