Top 10 Summer Flowering Shrubs
Attract hummingbirds and butterflies with these summer flowering shrubs that provide a robust nectar source in your own backyard.
Gorgeous springtime blossoms…fantastic fall color…tasty winter berries: When it comes to shrubs, these come to mind first. But superb summertime blooms? Yes, actually! You can find a whole slew of shrubs that flower in summer, which makes them outstanding nectar sources for hummingbirds. So we couldn’t think of a more fitting issue than our annual hummingbird special for our Top 10 summer-blooming shrubs. Add a couple of these summer-blooming shrubs to your backyard, and you’ll keep the hummingbirds (and butterflies) happy for years to come.
Carol L. Edwards
Summer Flowering Shrubs: Butterfly Bush
(Buddleja davidii, Zones 5 to 9)
With arching spikes full of purple, white, pink or yellow florets, butterfly bush will bloom from midsummer through the first frost. Gardeners prize it for its impact—it can grow up to 15 feet, with hundreds of blossoms—and because it will endure drought and heat. Plant in full sun. Note that it’s considered invasive in some areas, though new varieties are seedless; check before planting.
Favorites: The new choices are many, including several smaller varieties. Look for the Lo & Behold Blue Chip cultivar, which grows to only a couple of feet, or the English Butterfly Peacock, which tops out at about 5 feet.
(Philadelphus, Zones 3 to 8)
Once you see mock orange, you’ve got to have it. In early summer, the summer flowering shrubs bear gorgeous pure white flowers that last for weeks and smell delicious. Most grow up to 6 feet tall, but you can also find compact or dwarf varieties. Grow in full sun.
Favorites: Look for Snow White Sensation, with its resplendent double blooms. It will flower in late spring or early summer and then will bloom again later in the season.
(Spiraea, Zones 3 to 8)
If you want an easy-to-grow summer flowering shrub with exciting color, look for a spirea at the garden center. While they provide several seasons of interest, it’s the summer blooms that are impressive. Sure, the individual flowers are tiny, but together they pack quite a punch. Spirea prefers full sun. It’s important to find a cultivar that’s right for your space—some grow only 18 inches tall, while others can get to be several feet.
(Potentilla fruticosa, Zones 2 to 7)
It’s one of the longest-blooming shrubs around, beginning to flower in late spring and then continuing until fall. Northern gardeners love it because it does well even in frigid Zone 2. Potentilla loves full sun and well-drained soil; blooms are typically yellow. The shrub is on the small side, from 1 to 4 feet tall, usually with a mounding habit.
(Caryopteris, Zones 5 to 9)
If you long for blue flowers, this bold little summer flowering shrub could provide exactly what you’re looking for. Most grow to only 2 or 3 feet high in full sun, making them a good shrub for a small space. The deep blue flowers emerge in late summer and keep right on blooming through fall. This one’s a favorite of butterflies, too.
(Viburnum, Zones 2 to 9)
Among the most popular of ornamental shrubs and small trees, viburnum is sought after for three reasons: It’s handsome, it’s versatile and it’s easy to grow. Truly a year-round shrub, it rewards you with flowers in spring or summer, appealing foliage in fall and berries from fall to winter. Grow in full sun or part shade.
Rose of Sharon
(Hibiscus syriacus, Zones 5 to 9)
When other flowers are spent, this late bloomer becomes a generous source of energy for hummingbirds. A member of the hibiscus family, it bears charming trumpet-shaped flowers that bloom from late summer through midautumn. In optimal conditions, including moist, well-draining soil and lots of sunshine, rose of Sharon can climb to 10 feet or more.
Favorites: We love the classic rose of Sharon, but two new cultivars introduced by Minier Nursery in France are really getting our attention, too—Tahiti, with deep pinkish-purple blooms, and Fiji, with unique semidouble fading blooms and dark red centers.
(Lagerstroemia indica, Zones 7 to 9)
Crape myrtle is a year-round favorite in the South, where it thrives in the warmth and blooms from July to September. The spectacular flowers won’t stop attracting butterflies, bees and hummingbirds. You can even remove the first wave of flowers to encourage a second bloom. Grow this heat-tolerant beauty in full sun, and it might get to be 10 feet or more.
Favorites: Purple Magic is a new crape myrtle that is considered a semidwarf variety, with clusters of dark purple blooms. It’s a champion grower, bred for resistance to leaf spot and powdery mildew.
(Clethra alnifolia, Zones 4 to 9)
While it often flies under the radar, summersweet is a trustworthy summer flowering shrub that beckons butterflies and hummingbirds. (In fact, one cultivar is so popular it has hummingbird in the name.) Grow summersweet in full sun to partial shade. Blooms emerge in midsummer; even when the flowers fade, you’ll still get pretty fall color from the foliage. This is one unfamiliar shrub you’ll want to take a chance on.
Favorites: Hummingbird Summersweet is a cultivar with wonderful fragrant flowers and compact growth. As the name promises, hummingbirds will flock to your yard for its abundant blossoms.
(Hydrangea, Zones 3 to 10)
Gardeners have relied on hydrangeas for years to provide showy summer color. Easy to care for, they happily flower even in partial shade. Bigleaf hydrangeas (Hydrangea macrophylla) are ideal for mild climates but usually won’t flower in regions with cold winters. In those areas, try cultivars of sevenbark hydrangea (Hydrangea arborescens), which typically produce big white blooms.