Hydrangea pottingeri Prain — Chinese hydrangea

Introduction

Chinese hydrangea (Hydrangea pottingeri) is a woody shrub of Hydrangea subg. Dichroa sect. Chinenses and the nomenclatural successor to the species long known as H. chinensis Maxim. In its narrower modern sense, it is an upright deciduous shrub commonly 0.5–4 m tall, with relatively thick lanceolate, narrowly elliptic, or obovate leaves, terminal corymbose inflorescences, three or four enlarged white to yellowish marginal sepals, and small fertile flowers with yellowish petals. The stamens are usually 8–11 and subequal, the ovary is approximately half superior, and the seeds are essentially wingless.

The familiar name Hydrangea chinensis was replaced for nomenclatural reasons rather than because the species itself was redefined. The earlier name H. sinensis Standish & C.Noble ex Hérincq creates a nomenclatural conflict with H. chinensis Maxim.; current Kew treatment therefore accepts H. pottingeri Prain as the available species name. The sectional name Chinenses, however, is unaffected.

That apparently simple name change overlays a much more complicated biological history. The traditional H. chinensis concept was progressively expanded to absorb a number of localized Chinese, Taiwanese, Japanese, and Philippine taxa, and McClintock (1957) went further by including much of this diversity within a broad H. scandens. Modern phylogenetic work has demonstrated that the resulting complex is not a single lineage: Yang et al. (2024) separated several Japanese and Taiwanese elements into sect. Kawagoeanae, while retaining a more restricted mainland-centered Chinenses.

Tree TSAR therefore treats H. pottingeri as the core lineage corresponding broadly to H. chinensis sensu stricto rather than as a repository for every morphologically similar East Asian hydrangea. H. linkweiensis and H. mangshanensis are accepted separately, H. lobbii belongs in sect. Kawagoeanae, and Tree TSAR also restores H. stenophylla as a species. Current POWO still includes H. stenophylla among 16 synonyms of H. pottingeri, illustrating how strongly the broader historical concept persists in taxonomic backbones.

Comparison with Hydrangea stenophylla

Character	**Hydrangea pottingeri**	**Hydrangea stenophylla**
Habit	Shrub ca. 0.5–4 m	Shrub ca. 0.8–2 m
Younger stems	Reddish to brown	First-year shoots purplish
Second-year stems	Brownish; bark commonly exfoliating	Usually gray-white to white; bark not peeling at this stage
Leaves	Lanceolate, narrowly elliptic or obovate; usually 5–12 × 1.5–4 cm	Narrowly lanceolate to lanceolate; usually 8–20 × 1–2.7(–4.5) cm
Lateral veins	Usually 4–7 pairs	Usually 7–10 pairs
Inflorescence	Terminal, essentially sessile	Pedunculate, peduncle ca. 4–12 cm
Fertile petals	Yellowish, ca. 3 mm	Green-white, ca. 3–4 mm
Capsule	Globose to fusiform/ovoid	Broadly ellipsoid
Classical range	Broad eastern and southern Chinese complex, extending westward under some treatments	Northern and western Guangdong, southwestern Jiangxi
Plastid evidence	Core chinensis/pottingeri lineage	Distinct lineage; not recovered with core pottingeri
Tree TSAR	Accepted	Accepted, restored from synonymy

The distinction is important because H. stenophylla is not merely a narrow-leaved extreme of H. pottingeri. Its pale second-year branches, numerous lateral veins, long-pedunculate inflorescences, green-white petals, and different fruit shape form a correlated morphological syndrome. Flora of China recognized it independently, and Yang et al. (2024) sampled it as a distinct lineage within sect. Chinenses.

The remaining synonymy of H. pottingeri still contains unresolved historical material. Tree TSAR retains names such as H. umbellata, H. chloroleuca, H. jiangxiensis, and H. chinensis var. patentihirsuta provisionally within the species. Taiwanese H. glabrifolia and H. angustipetala var. major require future type-level reassessment, while the Philippine H. pubiramea complex is best treated as unresolved rather than confidently assigned here. Current specialist horticultural treatment likewise emphasizes that naming material in the pottingeri/scandens complex remains exceptionally difficult.

Horticultural and Agricultural Uses

Chinese hydrangea has reached Western cultivation through several modern wild collections, including material from Taiwan, Arunachal Pradesh, Sichuan, and Yunnan. It is still more experimental than mainstream as a garden shrub. Young plants can be attractive, with relatively thick foliage and early lacecap-type flowering, but older specimens may become tall and somewhat open or leggy. Light shade appears appropriate, and different provenances probably vary substantially in cold tolerance. Trees and Shrubs Online gives an approximate USDA range of zones 8–9 and RHS H4.

The horticultural value of authentic material is amplified by the taxonomic confusion surrounding the species. Provenance and collector numbers should be retained whenever possible because cultivated plants labelled H. chinensis or H. pottingeri may actually represent H. angustipetala, H. lobbii, or another segregate of the historical complex.

No major agricultural use is documented.

Conservation Concerns

No formal global IUCN Red List assessment was located for Hydrangea pottingeri. Specialist treatment lists the species as not evaluated, while POWO currently gives a broad native range from Arunachal Pradesh through northern Myanmar to southeastern China.

The principal conservation complication is taxonomic. Historical records under H. chinensis, H. scandens, or broad H. pottingeri can include multiple evolutionary lineages. Apparent geographic breadth therefore cannot automatically be translated into population security. Conservation assessments should be based on voucher-confirmed populations under the narrower species concept, particularly where southeastern Chinese, Taiwanese, and southwestern Chinese material meet.

Additional Information

Plants of the World Online — Hydrangea pottingeri (opens in a new tab): — Current accepted nomenclature, distribution, and broad synonymy.

Trees and Shrubs Online — Hydrangea pottingeri (opens in a new tab): — Detailed modern horticultural and taxonomic treatment of the pottingeri/scandens complex.

Flora of China — Hydrangea chinensis (opens in a new tab): Morphological treatment corresponding broadly to the familiar historical concept of the species.

References and Further Reading

McClintock E (1957) A monograph of the genus Hydrangea. Proceedings of the California Academy of Sciences, Fourth Series 29(5): 147–256. https://www.biodiversitylibrary.org/part/51707 (opens in a new tab) https://doi.org/10.5281/zenodo.15905786 (opens in a new tab)

Sutton J (2025) Hydrangea pottingeri. Trees and Shrubs Online. International Dendrology Society. https://www.treesandshrubsonline.org/articles/hydrangea/hydrangea-pottingeri/ (opens in a new tab)

Wei Z, Bartholomew B (2001) Hydrangea. In: Wu ZY, Raven PH (eds.) Flora of China, vol. 8. Science Press, Beijing & Missouri Botanical Garden Press, St. Louis, pp. 411–422. https://www.iplant.cn/foc/pdf/Hydrangea.pdf (opens in a new tab)

Wei ZF (1994) A revision of the genus Hydrangea in China. Guihaia 14(2): 101–121. https://www.guihaia-journal.com/gxzwen/ch/reader/create_pdf.aspx?falg=1&file_no=199402002&quarter_id=2&year_id=1994 (opens in a new tab)

Yang X, Xue T, Gao T, Liang Y, Smets EF, Gadagkar SR, Yu S (2024) An updated infrageneric classification based on phylogenomics and character evolution in Hydrangea (Hydrangeaceae). Taxon 73(2): 503–518. https://doi.org/10.1002/tax.13158 (opens in a new tab)