Hydrangea fauriei (Hayata) Y.De Smet & C.Granados — Taiwanese hydrangea vine

Introduction

The Taiwanese hydrangea vine, Hydrangea fauriei, is a deciduous, aerial-rooting woody climber of Section Schizophragma and the section's characteristic Taiwanese representative. Mature leaves are ovate to broadly ovate and usually entire or only slightly serrulate near the apex. Their lower surfaces are glaucous and bear brown pubescence concentrated especially along the principal veins and in the vein axils, at least when young. This distribution of hairs is an important distinction from H. schizomollis, whose lower leaf surface is densely tomentose across much more of the lamina, and from H. glaucescens, whose leaves are largely glabrous beneath except for conspicuous tufts of hairs in the vein axils (Liu & Zhu 2011; Sutton 2025).

The securely documented core of the species is Taiwan, where herbarium records extend across several parts of the island and plants climb rocks and trees in forest. Liu & Zhu's revision treated H. fauriei as Taiwanese, and the modern Taiwanese plant-information system documents numerous specimens from the island. Flora of China and the current Kew backbone also report Fujian on the Chinese mainland, however. Because this mainland occurrence conflicts with the focused revisionary treatment, Tree TSAR regards Taiwan as secure and Fujian as requiring verification from the underlying specimens, rather than silently expanding the range.

The species has moved repeatedly between species and varietal rank. Hayata described Schizophragma fauriei in 1906 from Taiwanese material collected by Urbain Faurie. He subsequently treated it as S. hydrangeoides var. fauriei and later as S. integrifolium var. fauriei. All three names are homotypic and are now placed beneath Hydrangea fauriei by Kew. Their history illustrates an important feature of Section Schizophragma: superficially similar climbing plants were repeatedly assembled under broad continental or Japanese species concepts before focused morphological and anatomical work restored several regional lineages.

Modern molecular evidence adds a useful evolutionary perspective. In the plastome-based phylogeny of Yang et al. (2024), the sampled Taiwanese H. fauriei is recovered as the sister of mainland H. schizomollis. That relationship has good but not maximal bootstrap support and is biologically plausible given the two species' similar largely entire leaves and prominent abaxial indument. Their strongest practical difference lies in its distribution: the pubescence of H. fauriei is concentrated predominantly on the principal veins and vein axils, whereas H. schizomollis develops dense brown tomentum across the lower surface. The phylogeny therefore suggests a useful Taiwan–mainland evolutionary comparison without eliminating their morphological and geographic distinction.

Species rank remains well justified under the present Tree TSAR framework. H. fauriei combines a recognizable morphology with a strongly structured island distribution and is recovered as a distinct terminal in the best available phylogenomic framework. Population-level nuclear sampling across Taiwan would nevertheless be valuable, especially if authentic Fujian material can be located, because confirmation of mainland populations would materially alter the species' biogeographic interpretation.

Horticultural and Agricultural Uses

Among the less familiar members of Section Schizophragma, Hydrangea fauriei has developed a meaningful horticultural presence. Western cultivation expanded particularly through wild-origin Taiwanese collections made by Crûg Farm, including BSWJ and CWJ accessions, while material collected by Dan Hinkley has also circulated commercially. Established plants can produce vigorous climbing growth and large summer inflorescences and may retain foliage unusually late under favorable conditions. Sutton consequently regards the species as an increasingly important ornamental climbing hydrangea rather than merely a botanical curiosity.

Its horticultural identity nevertheless requires care. The cultivar ‘Plooster’, sold under the WINDMILLS™ trade designation, has circulated under H. fauriei, H. ampla, and H. hydrangeoides. Sutton considers H. fauriei the best current morphological fit because of its essentially entire leaf margins, but the species attribution has never been secure. ‘Angel Wings’ is likewise marketed as a large-flowered schizophragma without a securely documented wild origin. These plants should therefore be discussed as horticultural selections associated with H. fauriei, not used as evidence for the morphology or distribution of wild populations.

The species' growing representation in cultivation also creates an opportunity for research. Wild-origin accessions with retained collection numbers could be compared genetically with Taiwanese herbarium and field populations and with any alleged Fujian material. In a taxonomically difficult climbing lineage, well-provenanced horticultural collections can therefore serve both ornamental and systematic purposes.

Conservation Concerns

No formal global IUCN assessment was located for Hydrangea fauriei. Kew's Angiosperm Extinction Risk Predictions currently places it in the predicted-not-threatened category with confident model support, but this is a model-based screening assessment rather than a formal Red List evaluation (Bachman et al. 2024; Royal Botanic Gardens, Kew 2026).

Conservation interpretation is complicated by the unresolved range. If the focused revisionary view is correct and H. fauriei is effectively Taiwanese, it represents an island lineage with substantially greater biogeographic concentration than Kew's Taiwan-plus-Fujian distribution suggests. Conversely, verified Fujian populations would broaden its geographic basis considerably. Confirming the identity of mainland records should therefore be treated as a conservation as well as a taxonomic priority.

Taiwanese populations occur in montane forests and other wooded habitats, and substantial herbarium representation indicates that the species is not known only from a handful of historical collections. Nevertheless, cultivated abundance cannot substitute for information on the condition and continuity of wild populations. Modern occurrence mapping and population-genetic sampling would provide a stronger basis for assessment.

Additional Information

Plants of the World Online — Hydrangea fauriei (opens in a new tab): current accepted nomenclature, three homotypic synonyms, and the Taiwan–Fujian backbone distribution.

Trees and Shrubs Online — Hydrangea fauriei (opens in a new tab): detailed morphology, cultivation history, introductions, and discussion of the disputed Fujian occurrence.

Taiwan Plant Information Integration System — Hydrangea fauriei (opens in a new tab): Taiwanese nomenclatural history, morphology, vernacular names, and specimen records.

References and Further Reading

Bachman SP, Brown MJM, Leão TCC, Nic Lughadha EM, Walker BE (2024) Extinction risk predictions for the world's flowering plants to support their conservation. New Phytologist 242(2): 797–808. https://doi.org/10.1111/nph.19592 (opens in a new tab)

De Smet Y, Granados Mendoza C, Wanke S, Goetghebeur P, Samain M-S (2015) Molecular phylogenetics and new (infra)generic classification to alleviate polyphyly in tribe Hydrangeeae (Cornales: Hydrangeaceae). Taxon 64(4): 741–753. https://doi.org/10.12705/644.6 (opens in a new tab)

Liu W, Zhu X-Y (2011) Leaf epidermal characters and taxonomic revision of Schizophragma and Pileostegia (Hydrangeaceae). Botanical Journal of the Linnean Society 165(3): 285–314. https://doi.org/10.1111/j.1095-8339.2010.01101.x (opens in a new tab)

Royal Botanic Gardens, Kew (2026) Hydrangea fauriei (Hayata) Y.De Smet & C.Granados. Plants of the World Online. https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:77152139-1 (opens in a new tab)

Sutton J (2025) Hydrangea fauriei. Trees and Shrubs Online. International Dendrology Society. https://www.treesandshrubsonline.org/articles/hydrangea/hydrangea-fauriei/ (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)