- 1). Identify the pruning mistake. Common pruning mistakes include taking too much off the top, cutting the branches flush with the tree trunk, and shearing shrubs into unnatural shapes. Some pruning mistakes are obvious because the shrub looks unnatural. Other mistakes are less apparent. Cutting too closely to the trunk leaves a shrub vulnerable to disease. Over pruning some flowering shrubs results in fewer (or no) blooms the next spring.
- 2). Limit pruning the first year to allow the shrub time to recover. Use hand pruners to cut back any suckers (unattractive little limbs that grow vertically out of branches), dead branches, closely spaced branches, or branches that are rubbing against each other. Dip the blades in a disinfectant (one part bleach to nine parts water) between cuts to avoid spreading disease. Don't do any other pruning for at least one to two years as the shrub recovers and begins to develop its natural shape.
- 3). Spray shrubs if they are plagued by disease or insects. Consult your local extension office for the best treatment for specific diseases and pests. Over pruning makes shrubs vulnerable to diseases, especially when branches are cut flush with the shrub trunk. To help shrubs recover from overpruning, apply a liquid fertilizer made for shrubs according to package directions.
- 4). Prune shrubs selectively once they've developed new growth. To let in more light, remove inner branches at the collar of the branch. (About 1/4 inch from where the branch and trunk intersect, you'll see a ridge. This is the collar.) Remove any branches that grow vertically or seem to detract from the shrub's natural shape.