Limelight hydrangea is a varietal of panicle form hydrangea that blooms in a unique pale green color evolving to either white or pink as the bloom head ages. This flowering perennial blooms in the summer and fall and will reach up to 8 feet in height at maturity. Limelight hydrangea is hardy in USDA zones 3 through 8. Prune in late winter after the blooms fade or in early spring before new growth appears.
Harvest blooms at their peak of beauty for use in cut flower arrangements. Cut down the blooms on mid-size to long stems at the desired length. Place the cut at least 1/4 inch above a leaf node on every stem.
Inspect the hydrangea each week when watering to look for damaged, diseased or dying foliage and branching. Cut back any damage that you find with clean secateurs again, always at least a 1/4 inch above a leaf node to preserve branching. Discard any diseased cuttings in the trash, bypassing the compost bin.
Hard prune your limelight hydrangea in the late winter or early spring after all blooms have faded and died back. Prune the stems to create an attractive and symmetrical branching structure. Be sure to collect all of the cuttings so that no foliage is allowed to rot on the soil, which can invite disease.