Even with its lovely clumps of delicate white flowers, spirea is actually one of the easiest shrubs to grow. Spireas can be planted in less-than-perfect soil, they can thrive in sun or shade and they produce masses of blooms every spring with very little attention. Although it isn't required, a good pruning will keep your spirea looking neat and shapely, and will encourage even more blossoms.
Prune spirea in late winter or early spring. Although 6 to 8 inches is usually enough to stimulate new growth and will preserve the spirea's natural shape, it's safe to remove up to 30 percent of the bush.
Remove any dead branches or wood that looks weak or diseased. This will provide air circulation, and will allow energy to go to the healthy branches.
Clip off blooms as soon as they fade and turn brown. You can also cut fresh blooms, which make a lovely bouquet. Trim the branches again after the spire has finished blooming for the season.