One of the most popular flowering bushes across America, Hydrangeas are a beautiful addition to any landscape. They are bushes with beautiful flowers that bloom in a variety of colors based on species and soil acidity. In the middle of summer, the full color of Hydrangea bushes truly show the most vibrancy, but they can begin their bloom in the late spring, providing color for much longer than most plants. Such a prolonged bloom period commonly brings up the question of when the best time to prune a hydrangea is. There are two different types of hydrangeas based on the way they flower. One type sets flower buds on “old wood” where as the other type produces buds on “new wood”.
Old Wood Bloomers
Basically the “old wood” distinction is given to plants which flower on the stems from the previous years growth. The most common varieties which fall under the “old wood” distinction would be the mop head, lacecap, and big leaf types (Hydrangea macrophylla), and the Oakleaf hydrangea (Hydrangea quercifolia). These hydrangeas should be pruned only after bloom in the summer and not in the fall. The bloom buds begin to develop for the following year in August and September. By not following this protocol would result in cutting off of the potential flowers for the following season. The proper pruning method would be to first remove all the dead stems from the plant, then reduce the plant by up to 1/3 of its current size. Do not cut the plant all the way to the ground.
New Wood Bloomers
The “new wood” distinction is given to plants which flower on the new growth for that season. These are very easy to care for since they bloom every year regardless of how they are treated. This group of hydrangeas would include the PeeGee types (Hydrangea paniculata) and the Annabelle types (Hydrangea arborescence). The PeeGees can be pruned in the fall or winter and can be trained into trees but should never be cut to the ground. The Annabelle can be pruned to the ground when dormant, however by doing this repetitively could result in weaker stems that may need to be staked.
There is one plant which defies the previous two distinctions known as the ‘Endless Summer’ variety. These hydrangeas bloom both on old and new wood. It blooms in the spring on old wood then later in the summer on new wood. By cutting off faded flowers to half their length will encourage new growth and buds. It can be pruned after the last bloom of the season in the fall to shape.
Wiesner Bros. Nursery has been serving the Staten Island community for generations. With the largest Nursery in New York city and our full garden center, our experts can help you design your dream garden for your dream home. For more information, call 718-761-5141 or e-mail us.