These hydrangea varieties produce new growth each spring, then bloom from that growth later in the summer. They tend to bloom later than hydrangeas that bloom on old wood, since varieties that produce new wood need that extra time to create buds. The following varieties bloom on new wood:   Panicle hydrangeas (H. paniculata), such as PeeGee or Limelight. These can be pruned into a tree form to make it a focal point of the garden.  Smooth hydrangeas (H. arborescens), such as Annabelle Use the images at http://www.hydrangeashydrangeas.com/identify.html to help you identify what kind of hydrangea you have before you start making any plans to prune your plant. Since these varieties produce their blooms on new stems, you want to prune them in the winter before they start growing. This is the best time of year to prune new wood varieties, but you can prune them at other times of year as well - just avoid pruning them right before they're about to bloom in the spring and early summer.   You can cut back all the stems by 1/3 in the winter. Pruning at this time will help the shrub produce bigger, showier flowers. However, many gardeners like their hydrangeas to have smaller flowers on sturdier stems. If this is your preference, do your pruning in the fall instead, to allow the plants to grow strong branches before blooming. Use hand shears or loppers to take out dead canes and branches that are crossed or tangled. This will free up the plant and allow for better airflow, encouraging it to grow stronger. Hydrangea flowers tend to be on the heavy side, so don't go overboard pruning old canes. Leave a good network of canes intact so that the branches don't flop over under the weight of the flowers.

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