How to Prune Overgrown Spirea in August
- 1). Look for all dead or diseased stems that are brown, black or have spots and prune them off at the surface of the ground. Wipe the blades of the hand pruners or loppers on an alcohol-soaked rag to disinfect them before proceeding.
- 2). Examine each of the spirea stems and identify those that have little or no foliage or that failed to bloom during the season. Cut these stems off flush with the surface of the ground using hand pruners for thin stems and loppers for any that are thicker than 1 inch in diameter.
- 3). Identity the oldest stems on the spirea, which are typically near the center of the plant and are the tallest. Cut one-third to one-fourth of these stems back flush with the ground as well using the loppers. This technique opens up the plant to air and light and encourages additional blooms and foliage.
- 4). Grasp one of the remaining stems in your hand and trace it back to the first bud below the tip. The buds look like tiny, pea-like projections. Cut the stem off using hand pruners 1/4 inch above the bud and making the cut straight. Repeat the process to cut back the tips of each remaining stem in the same manner.
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