Hydrangea luteovenosa in Rhododendron Glen at the Arboretum. (Photo by Niall Dunne)
BY REBECCA ALEXANDER & NIALL DUNNE
This regular column features Q&A selected and adapted from the Elisabeth C. Miller Library’s Plant Answer Line program. If you’d like to ask a plant or gardening question of your own, please call (206) 897-5268 (UW Plant), send it via the library website (www.millerlibrary.org), or email directly to hortlib@uw.edu.
QUESTION
I want to add a hydrangea to my garden, but I would prefer one that is also fragrant. Are there varieties that have a noticeable pleasant scent?
ANSWER
Hydrangeas are celebrated for their showy, late-spring and summer flowerheads, but, as a group, they don’t have a great reputation for producing fragrant blossoms. Many of the varieties popular in gardens today are described as “non-scented” or—at best—“faintly scented.”
However, Hydrangea is a relatively large genus, containing about 70 species of shrubs and vines native to Asia and the Americas, and some of these do produce flowers with a noticeable perfume.
The Vagaries of Plant Scent
Bear in mind, though, that everyone’s sense of smell is different, and fragrances that are pleasant to some can be off-putting or even imperceptible to others. (Moreover, flower fragrance is an adaptation that helps many plants attract insects and other pollinators. And while a plant may seem “unscented” to human nostrils, its pollinators might beg to differ.)
Another thing to keep in mind is that environmental and biological factors such as temperature, humidity, and age of the flowers can play a role in how a plant’s fragrance is perceived. Flowers tend to be more fragrant on warm, humid days, which helps the plant’s volatile aromatic compounds evaporate more readily. Conversely, dry, windy conditions can quickly dissipate these scent compounds.
Before making a purchase, we recommend seeking out examples of the plants in bloom in nurseries, botanic gardens, or large parks and doing a sniff test on the flowers. Washington Park Arboretum has a fine selection of hydrangeas, concentrated heavily in and around Rhododendron Glen and the north end of the Camellia Collection grove.
Oakleaf hydrangea (Hydrangea quercifolia) in the Woodland Garden. (Photo by Niall Dunne)
Oakleaf and Panicle Hydrangeas
The smell of oakleaf hydrangea, Hydrangea quercifolia, is a rich honey-vanilla to Rebecca’s nose. Native to the U.S. Southeast, this deciduous shrub grows about eight feet high and wide and produces large, lobed, oak-leaf-like foliage. From May to July, it bears stunning, pyramidal clusters of white flowers that are a wonderful magnet for honeybees, bumblebees, pollen wasps, and syrphid flies.
As with most hydrangeas, the flowerheads of oakleaf hydrangea are made up of tiny, fertile, inner flowers and more dramatic, but sterile, outer flowers. In Rebecca’s garden, all the pollinator activity is humming along on the fertile inner flowers; however, the sterile, conspicuous flowers do serve an important visual function, signaling to pollinators and directing traffic to the fertile flowers.
Panicle hydrangea, Hydrangea paniculata, is a large deciduous shrub native to China, Japan, Sakhalin, Taiwan and Kuril Island. Typically growing up to 15 feet tall, it produces oval-shaped, serrated leaves and large, bold, conical clusters of creamy-white summer flowers, similar to those of oakleaf hydrangea. The flower scent is often described as lightly sweet or fruity.
Many cultivars (cultivated varieties) of the plant have been developed, and even though these tend to emphasize the eye-catching sterile flowers over the fertile ones, some of them, such as ‘Jane’, ‘Limelight’, ‘Phantom’, and ‘Vanilla Strawberry’ are said to have subtle, fruity fragrances.
Hydrangea paniculata ‘Jane’ in the Centennial Summer Garden. (Photo by Niall Dunne)
Himalayan and Nettle-Leaf Hydrangeas
A species that has been planted a lot in the Arboretum recently is the Himalayan hydrangea, Hydrangea heteromalla, a close relative of H. paniculata. A large, deciduous shrub from the Himalayas and China, it can grow up to 15 feet tall and also take on the form of a small tree. It is prized for its large, elliptical foliage, which is dark green on top and has velvety, silver-grey hairs underneath.
Flap-topped, lace-cap-like flowerheads appear from late spring to early summer and are a big draw for pollinators. Niall recently visited the large specimen in the China Entry Garden at the Arboretum and did a sniff test. He says that if you stick your “schnoz” close to the small, fertile flowers in the center of the flowerhead, you should enjoy a pleasing, fruity aroma.
Not that far north of the China Entry Garden, in the open glade of the Arboretum’s main Camellia Collection, is a grouping of hydrangeas that includes the Japanese species Hydrangrea hirta, or nettle-leaf hydrangea. A small deciduous shrub that only gets up to five feet high, it produces coarsely serrated, stinging-nettle-like foliage (without the stinging hairs). Its flat-topped, summer flowerheads are unusual for hydrangeas, as they are made up only of small, fertile flowers.
Here’s what the International Dendrological Society says about the plant and its fragrant flowers: “Unmistakable once seen, this Japanese endemic is far too rarely grown in Western gardens. Individual inflorescences are small and lack showy sterile flowers, but the shrub’s growth form brings them together on flat-topped clumps which assort well with herbaceous plants in the mixed border. Their sweet smell, resembling meadowsweet (Filipendula ulmaria), is also worthwhile in the summer garden.”
Hydrangea heteromalla in the China Entry Garden. (Photo by Niall Dunne)
A Fragrant Species Complex
Though harder to find in nurseries, a number of closely related species hydrangeas from Asia offer strong and pleasing scents. One is Hydrangea luteovenosa, a small (four-foot high), elegant deciduous shrub native to Japan and South Korea. It produces gently arching purple stems and narrow, willow-like leaves. Loose, sweet-scented, lace-cap flowerheads appear in late spring and consist of small, yellow fertile flowers and large, white sterile flowers.
You will find a lovely specimen of Hydrangea luteovenosa in the upper rim of Rhododendron Glen, where the Lookout Loop Trail connects to the mulched pathway that features the Arboretum’s main hydrangea collection. The specimen was a gift from Heronswood Garden and was collected by explorer Dan Hinkley on Japan’s Shikoku Island in 1997.
Hydrangea luteovenosa is one of several fragrant species—including Hydrangea scandens, from Japan, and the Chinese hydrangea, H. chinensis—that form a species complex, which is a group of plants that are so similar in appearance that the boundaries between them are unclear.
Dan Hinkley has written about them in “Horticulture” magazine (“Horticulture,” Jun/Jul 2009, Vol. 106, Issue 5) and the two fragrant cultivars he selected. Hydrangea angustipetala (now H. chinensis) and its cultivar ‘Golden Crane’ (also called ‘MonLongShou’) are said to smell strongly like jasmine or sweet alyssum. Of the species, Dan Hinkley says, “The deeply scalloped sepals of the infertile florets surround a disk of striking chartreuse fertile flowers while emitting a faint but beguiling fragrance.”
Of Hydrangea scandens, Dan says, “As its name implies, it can be a sprawling shrub but far from what would be considered disheveled. The branches possess a pleasing burgundy-brown color and the lacy, cream-colored flowers pack a powerful fragrance. Hydrangea scandens ‘Fragrant Splash’ adds a bonus of variegated foliage.”
When we contacted Dan, he again urged caution about the vagaries of plant scent: ‘Golden Crane’ and ‘Fragrant Splash’ are the two that I think of as fragrant. With that said, some gardeners find no fragrance at all in the former, while others find the latter disagreeable.”
Hydrangea hirta in the Camellia Collection area. (Photo by Niall Dunne)
There’s no substitute for personal experience! And you can find three specimens of Hydrangea chinensis in the Arboretum, all generously donated by Dan to the Rhododendron Glen restoration project back in 2018. The trio are planted together in the lower glen by the restored streambank, and bloom time is late spring to early summer.
Rebecca Alexander is the former manager of Reference and Technical Services at the Miller Library, located in the UW Botanic Gardens’ Center for Urban Horticulture (3501 NE 41st Street, Seattle). Niall Dunne is the editor of the “Arboretum Bulletin” and the communications manager at the Arboretum Foundation.
References
- Candeias, M. “The Sterile Flowers of Hydrangea.” “In Defense of Plants” blog. June 28, 2027.
- Hans, T. “Most Fragrant Hydrangea Varieties to Add to Your Garden.” “Garden Fine.” June 23, 2023.
- Sutton, J. “Hydrangea hirta,” from the website “Trees and Shrubs Online.” 2025.
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This article is reprinted from the summer 2026 issue of the Arboretum Bulletin, our quarterly botanical and horticultural magazine. Published since 1937, the Bulletin is a benefit of Arboretum Foundation membership and features in-depth articles on the Arboretum collections and history, as well as general information of interest to plant lovers in the Pacific Northwest and beyond. Join/subscribe today.
