Summertime blooms create ongoing interest in the landscape. Bright and bold flowers that can be seen from inside the home are essential to a well-designed plan. One such plant that fits this bill is the Hydrangea paniculata, or panicle hydrangea.
Panicle hydrangeas are old-fashioned plans that have been reinvented through modern breeding. They come in a number of selections with large, showy flowers in varying heights that will tolerate a Midwest summer with just a little care.
Panicle hydrangeas are noted for their summer blooms. Flowering starts in early July and lasts through summer and into fall. Their blooms are white with tinges of pink, depending on variety and weather patterns. The flowers are pyramidal panicles. Some varieties produce large, cone-shaped blooms reaching almost football size.
Unlike its fussier cousin, Hydrangea macrophylla — which includes Endless Summer hydrangea, bigleaf hydrangea, French hydrangea and lacecap hydrangea — maintenance for this panicle hydrangea is simple. Yearly pruning is a must. This plant flowers on the new growth that develops each spring. The ideal time to prune is late winter or early spring just before the plant breaks bud. Panicle hydrangeas can get big — up to 10 feet depending on the variety. The most impressive flower heads are produced with harder pruning to reduce shrub size as each new shoot terminates in the summer flower. Left unpruned the plant looks unkempt and flower size greatly decreases.
It grows best in well-drained soil, is not fussy about soil pH and will tolerate clay soils as long as the excess water drains during wet periods. The flower color is not pH-dependent like the Hydrangea macrophylla, as they bloom white.
Best flowering is achieved when the shrub receives ample sunshine. Full sun is best but a little afternoon shade will be tolerated.
Supplemental watering during dry spells promotes best growth and flowering. The foliage will wilt when it needs a drink, but water should perk it right back up. Poor flowering will occur in dry conditions.
Fertilization is rarely required. A two- to three-inch layer of wood chip mulch will break down and release enough food for good growth. The mulch will conserve moisture and keep the roots cooler during summer, helping it thrive.
The most difficult part of growing is deciding which variety to add to the garden. There are a number of wonderful selections on the market. The plants all have the same flower shape, but they can reach five feet or taller, depending on the variety. All varieties require the same care. The latest breeding trend is introducing pink shades in the usually white-only flowers.
If you are looking for summer color, look no further than the panicle hydrangea. Now is a great time to notice this plant in the KC landscape or at your local nursery, as they will be in full bloom this time of year.