How to Prune an Overgrown Hedge

Pro Tip: Roger Cook, This Old House landscape contractor, explains that severely overgrown hedges may require rejuvenation pruning — a more involved process where you take out one third of the oldest stems to allow sunlight into the center of the hedge. This technique takes more time and may require loppers and a chainsaw in addition to hedge trimmers, increasing both equipment costs and labor hours.

Pro Tip: Roger Cook, This Old House landscape contractor, explains the importance of timing: “You don’t want them to break bud before you prune because you want the plant’s energy to go toward producing new growth where you want it. If you take off a plant’s buds, you” lose that energy. Ideally, hedges should be pruned in late winter, when plants are dormant and haven’t produced buds — particularly if you’re cutting back drastically.

In this video, This Old House landscape contractor Roger Cook gives new life to an an out-of-control hedgerow.

Steps:

1. Drive a tall wooden stake into the ground at each end of the hedge.

2. Stretch a tight string between the stakes and tie off both ends. Position the string to represent the cutting height of the hedge.

3. Use a gas-powered hedge trimmer to slowly cut the hedge along the taut string.

4. To cut branches larger than 1 inch in diameter, use a pair of long-handle bypass loppers.

5. Remove and discard the branches trimmed from the hedge.

Why Shape Matters: When pruning an overgrown hedge, always taper it so the bottom is wider than the top. This lets more sunlight reach the base of the plant, encouraging fuller growth, and it also helps the hedge shed snow in wintertime, preventing broken branches.