Summer Flowering Shrubs
In spring, it seems that every shrub in town is in flower.
"Then summer comes and it seems that it's hard to find a flowering shrub anywhere," said Yiesla. "There are actually quite a few summer-flowering shrubs, but they are often overlooked , simply due to the time that the consumer is shopping. Most gardeners go shopping in spring, when they see spring-flowering shrubs in abundance. The summer bloomers get overlooked, because they are not showy in spring."
The hydrangeas are a good choice for summer flowering shrubs. Panicled Hydrangea (Hydrangea paniculata) is an old-fashioned favorite with many new varieties available. It is a medium to large shrub growing 10-15 feet tall. The large clusters of white flowers turn pinkish in late summer and then brown as the clusters persists on the shrub. Full sun to partial shade is best for this shrub.
Smooth Hydrangea (Hydrangea arborescens) is another favorite. The variety 'Annabelle' is very popular for its large round clusters of white flowers in summer. This shrub grows three to five feet tall and does best in partial to full shade. Oakleaf Hydrangea (Hydrangea quercifolia) also has large clusters of white flowers in summer. The leaves look like oak leaves and provide some red or russet fall color. This shrub grows three to six feet tall and can grow in sun or shade. A slightly protected site is best in northern gardens.
"For bright yellow flowers, look to the St. Johnsworts. Kalm St. Johnswort (Hypericum kalmianum) has bright yellow flowers in midsummer and blue green foliage all season," she said. "It grows only two to three feet tall and does best in full sun.
"Shrubby St. Johnswort (Hypericum prolificum) also has bright yellow flowers in midsummer. It is slightly larger (three to four feet) and can grow in full sun or partial shade."
Other mid-suumer bloomers include:
- Summersweet Clethra (Clethra alnifolia): four to eight feet tall; white flower spikes; full sun to partial shade.
- Buttonbush (Cephalanthus occidentalis): six to 12 feet; small balls of white flowers; full sun; good for wet sites.
Shrubs that flower in the latter part of summer include:
- Rose of Sharon (Hibiscus syriacus): nine to 12 feet tall; flower color depends on variety selected; flowering starts August; full sun or partial shade.
- Seven Sons Flower (Heptacodium miconioides): a large shrub (10-15 feet) with white flowers in late summer, followed by dry pink fruit in autumn that make it appear as though the shrub is flowering pink. Full sun to partial shade.
- Bluebeard (Caryopteris x clandonensis): a small shrub (2-3 feet) often sold as a perennial; small blue flowers in late summer and small tan fruit in winter. Can be cut down in early spring as it will bloom on new wood.