How to Trim Arborvitae Shrubs
- 1). Wait until early spring to prune the arborvitae shrub, just before it starts to produce new growth.
- 2). Look at the top of arborvitae shrub and make sure there is only one main vertical branch in the center. If there is more than one main branch, cut 3 to 6 inches off the tip of each remaining branch using pruning shears. Trim only the top one-third of the shrub in this manner.
- 3). Move down to the middle section of the shrub and cut the tips off here as well using the pruning shears. Reduce the amount that you cut off to between 3 and 4 inches so that the shrub starts to flare out slightly.
- 4). Move down to the bottom one-third of the shrub and trim 1 to 2 inches off the end of each branch using the punning shears.
- 5). Stand back and look at the overall shape of the shrub, which should be slightly conical. Trim the tips of any additional branches that stick out of the natural conical shape so that the outer edges slope smoothly downward.
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