Written by Tolly Beck
Tolly Beck is the horticulturist at Lasdon Park and Arboretum in Westchester County. She was formerly a horticulture educator for New York Botanical Gardens in the Bronx and Cornell Cooperative Extension of Rockland, NY.
What’s in Bloom at Lasdon
Kousa Dogwood Cornus Kousa
Hydrangea Hydrangea spp.
Spiraea Spiraea spp.
Viburnum Viburnum spp.
Weigela Weigela spp.
Astilbe Astilbe spp.
Beards tongue Penstemon digitalis ‘Huskers Red’
Daylily Hemerocallis spp.
Fairy Candle Actaea racemosa
Geranium Geranium sanguineum
Sunflower Heliopsis Heliopsis helianthoides
Yellow Corydalis Corydalis lutea
Native shrubs are often low maintenance, and many provide more than one season of interest. Summersweet (Clethra alnifolia) is one such native shrub, beginning with fragrant summer flowers that grow in upright narrow panicles in white or shades of pink. The nectar from these fragrant flowers is highly attractive to hummingbirds, butterflies, and bees. Blooms begin in July and last for 4-6 weeks. After flowering, seeds grow in fruit capsules that are attractive to birds.
The leaves of Summersweet are green to dark green in summer. They turn a golden yellow in fall, creating interest in the autumn landscape. There are a number of Summersweet cultivars which will influence the flower color as well as height. Some cultivars are only 3 feet high while others range up to 8 feet. This adaptable shrub prefers to grow in sun and sandy soils, but will tolerate shade and clay soils. Summersweet prefers evenly moist soil but will tolerate short periods of drought once it becomes established. Deer resistance is another prized attribute.
The next time you visit Lasdon come and see the Clethra growing in both the Synoptic Shrub Border and as foundation plants at the Conservatory. The native Clethra alnifolia grows to about 4- 6’ and produces white flowers. The Clethra cultivar ‘Hummingbird’ is a compact 2-3’ high and wide and also produces white flowers. Clethra ‘Ruby Spice’ is about 6 high and produces red buds that unfold to a deep pink flower. Summersweet provides an easy care shrub that is a nice addition to any landscape.