To prune a spirea bush, remove the tips at the beginning of spring, maintain the shape during the summer, remove overgrown stems and branches during the fall, and cut dead or damaged branches during the winter. Pruning shears are required.
- Trim the stem tips
After the first spring blossoms appear, use a pair of clean pruning shears to remove the tips of the stems back to the uppermost leaf bed on each individual stem. Be sure to keep the shape of the bush in mind as you go. This encourages new, healthy blooms.
- Maintain the plant's shape
During the summer, prune the bush regularly to keep its shape intact. If possible, cut overgrown shoots and stems within one-quarter inch of a leaf or bud. Disguise the cuts by trimming stems slightly shorter than surrounding stems and leaves.
- Trim as needed during the fall
During the fall, trim overgrown spireas and stems that are not producing dense foliage. Cut stems back approximately 8 to 12 inches above the ground. This helps the plant to produce new stems that flower during the spring.
- Remove dead and damaged branches
Check for dead or dying plant matter towards the end of winter, and remove it before swelling buds leaf out. Remove intrusive branches that are crowding other branches.