How to Prune a Spirea Hedge
- 1). Remove any branches that are dead or diseased. Cut them back to just about the first bud set above ground level.
- 2). Prune off the oldest branches, all the way to the first bud set above the ground. Do not remove more than one-third of the total number of main branches or the shrub may not be able to produce enough nourishment to recover.
- 3). Shape the spirea hedge by selectively pruning off the ends of branches so the top of the hedge is narrower than the bottom of the hedge. This is critical so that sunlight reaches the lower branches and leaves to maintain a hedge that is thick with growth all the way to the ground.
- 4). Head off the remaining branches. Make the pruning cut so that only about 2 inches of the previous year's new growth remains.
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