Late Panicle Hydrangea
Many gardeners are familiar with PeeGee hydrangeas (Hydrangea paniculata
‘Grandiflora’), often grown as a small tree and known for its large, showy flower clusters. Less well known but equally valuable in the landscape is late panicle hydrangea, a large shrub with late summer bloom.
Late panicle hydrangea grows about 6 to 8 feet tall and spreads 8 to 10 feet wide. The plant’s form is loosely rounded with upright stems. It has a medium coarse texture in all seasons.
This hydrangea has large, dark green leaves. Individual leaves are 3-5 inches long and 2-3 inches wide. The leaf margins are serrated. Late panicle hydrangea generally does not develop any fall color, though it may turn yellow at best.
Blooming in late summer (late August-early September), late panicle hydrangea provides a flower structure that is a somewhat cone shaped panicle about 6 inches long. Hydrangeas, including this variety, have an interesting combination of flower types within the inflorescence. There are both fertile and sterile flowers in the same flower panicle. The fertile flowers, which are capable of developing into seeds, are small, creamy white, and numerous. The sterile flowers are much larger and showier but less numerous. Cultivars such as ‘Grandiflora’ are selected because they have mostly sterile flowers. Making the flower cluster much larger and showier. However, the weight of these huge flower heads tends to pull down the branches of the plant. The panicles of ‘Tardiva’ have mostly small fertile flowers, with a nice sprinkling of the larger sterile flowers. I think this provides a more refined look, and the flower heads don’t weigh the branches down. The flowers are white, fading to pink as they age, then turning tan. The flowers will stay on the plant much of the winter. These flower heads are easy to dry and look wonderful in dried flower arrangements. Cut flower heads when they are fully open and hang up to dry in a warm, airy place.
Late panicle hydrangea is easy to grow. It prefers a moist, loamy soil but will tolerate many less than ideal soil conditions. Avoid constantly wet soil. Best flower production occurs when this shrub is planted in full sun, but it also tolerates quite a bit of shade. Late panicle hydrangea is relatively free of pest problems, though it may have an occasional attack of aphids, scales, or powdery mildew. Container grown plants can be planted anytime during the growing season. If you like to try plant propagation, this is a good one to try since it roots fairly easily from softwood cuttings taken in early summer.
Late panicle hydrangea can be used in various landscape situations as long as its large mature size is kept in mind. It can be planted in groups to fill a corner, line a driveway, or define a border. This large shrub is an excellent addition to a mixed shrub border, combine it with spring and early summer flowering shrubs and shrubs with winter color for all-season interest.