To prune forsythia bushes, cut back branches just before or just after the plant blooms. Cut older stems to the ground, trim back wayward canes and trim away canes that were trimmed in previous years. This can help make the shrub less dense and create a more uniform look.Continue Reading
Forsythia bushes can grow very tall, reaching heights and widths of up to 10 feet. It can be tricky to manage the size of a forsythia bush through pruning, but some carefully planned trimming can still help control a bush that is growing too large for its space. Pruning can also encourage flower growth, as it allows more light to reach the inner branches. To prune a forsythia bush, use the following steps.
Pruning a forsythia bush just after it blooms can allow gardeners to enjoy more of the blossoms. However, just before the bush blooms is also an appropriate time to prune, as it is easier to see the canes.
To start the pruning process, cut off old canes that have thick, woody stems. Cut these right down to the base.
Cut away any dead canes down to the ground.
If any stems are pointed in different directions or are drooping towards the ground, cut them off. This helps keep the plant from sprouting new plants and helps create a uniform look.
Pruning canes along the branch can cause new stems to grow in odd directions. If any canes were pruned this way in the past and are sprouting wayward growths, trim them to the ground.