Every accepted species in the genus is listed. A name links to its page when we hold at least three commercially licensed photographs of it. Where we do not, the row shows how many we actually found, which is usually none.
| Species | Authority | Usable photographs | Page |
|---|---|---|---|
| Hydrangea arborescens | L. | 473 | documented |
| Hydrangea quercifolia | W.Bartram | 248 | documented |
| Hydrangea chinensis | Maxim. | 207 | documented |
| Hydrangea barbara | (L.) Bernd Schulz | 199 | documented |
| Hydrangea macrophylla | (Thunb.) Ser. | 192 | documented |
| Hydrangea integrifolia | Hayata | 64 | documented |
| Hydrangea arguta | (Gaudich.) Y.De Smet & Granados | 58 | documented |
| Hydrangea aspera | Buch.-Ham. ex D.Don | 51 | documented |
| Hydrangea febrifuga | (Lour.) Y.De Smet & Granados | 45 | documented |
| Hydrangea involucrata | Siebold | 41 | documented |
| Hydrangea radiata | Walter | 37 | documented |
| Hydrangea serratifolia | (Hook. & Arn.) F.Phil. | 35 | documented |
| Hydrangea fauriei | (Hayata) Y.De Smet & Granados | 33 | documented |
| Hydrangea peruviana | Moric. ex Ser. | 29 | documented |
| Hydrangea scandens | (L.f.) Ser. | 29 | documented |
| Hydrangea viburnoides | (Hook.f. & Thomson) Y.De Smet & Granados | 24 | documented |
| Hydrangea hirta | (Thunb.) Siebold | 22 | documented |
| Hydrangea paniculata | Siebold | 22 | documented |
| Hydrangea longifolia | Hayata | 21 | documented |
| Hydrangea serrata | (Thunb.) Ser. | 12 | documented |
| Hydrangea hydrangeoides | (Siebold & Zucc.) Bernd Schulz | 10 | documented |
| Hydrangea densifolia | (C.F.Wei) Y.De Smet & Granados | 7 | documented |
| Hydrangea petiolaris | Siebold & Zucc. | 7 | documented |
| Hydrangea albostellata | Samain, Najarro & E.Martínez | 6 | documented |
| Hydrangea seemannii | L.Riley | 3 | documented |
| Hydrangea × mizushimarum | H.Ohba | 0 | below the evidence gate |
| Hydrangea acuminata | Siebold & Zucc. | 0 | below the evidence gate |
| Hydrangea alternifolia | Siebold | 0 | below the evidence gate |
| Hydrangea amagiana | Makino | 0 | below the evidence gate |
| Hydrangea amamiohsimensis | (Koidz.) Y.De Smet & Granados | 0 | below the evidence gate |
| Hydrangea ampla | (Chun) Y.De Smet & Granados | 0 | below the evidence gate |
| Hydrangea anomala | D.Don | 0 | below the evidence gate |
| Hydrangea asterolasia | Diels | 0 | below the evidence gate |
| Hydrangea bifida | (Maxim.) Y.De Smet & Granados | 0 | below the evidence gate |
| Hydrangea bretschneideri | Dippel | 0 | below the evidence gate |
| Hydrangea caerulea | (Stapf) Y.De Smet & Granados | 0 | below the evidence gate |
| Hydrangea chungii | Rehder | 0 | below the evidence gate |
| Hydrangea cinerea | Small | 0 | below the evidence gate |
| Hydrangea coenobialis | Chun | 0 | below the evidence gate |
| Hydrangea coenotialis | Chun | 0 | below the evidence gate |
| Hydrangea corylifolia | (Chun) Y.De Smet & Granados | 0 | below the evidence gate |
| Hydrangea crassa | (Hand.-Mazz.) Y.De Smet & Granados | 0 | below the evidence gate |
| Hydrangea daimingshanensis | (Y.C.Wu) Y.De Smet & Granados | 0 | below the evidence gate |
| Hydrangea davidii | Franch. | 0 | below the evidence gate |
| Hydrangea diplostemona | (Donn.Sm.) Standl. | 0 | below the evidence gate |
| Hydrangea fistulosa | (G.H.Huang & G.Hao) U.B.Deshmukh & M.B.Shende | 0 | below the evidence gate |
| Hydrangea glaucescens | (Rehder) Y.De Smet & Granados | 0 | below the evidence gate |
| Hydrangea gracilis | W.T.Wang & M.X.Nie | 0 | below the evidence gate |
| Hydrangea heteromalla | D.Don | 0 | below the evidence gate |
| Hydrangea hirsuta | (Gagnep.) Y.De Smet & Granados | 0 | below the evidence gate |
| Hydrangea hwangii | J.M.H.Shaw | 0 | below the evidence gate |
| Hydrangea hypoglauca | Rehder | 0 | below the evidence gate |
| Hydrangea jelskii | Szyszył. | 0 | below the evidence gate |
| Hydrangea kawagoeana | Koidz. | 0 | below the evidence gate |
| Hydrangea kwangsiensis | Hu | 0 | below the evidence gate |
| Hydrangea kwangtungensis | Merr. | 0 | below the evidence gate |
| Hydrangea lingii | G.Hoo | 0 | below the evidence gate |
| Hydrangea linkweiensis | Chun | 0 | below the evidence gate |
| Hydrangea liukiuensis | Nakai | 0 | below the evidence gate |
| Hydrangea longipes | Franch. | 0 | below the evidence gate |
| Hydrangea luteovenosa | Koidz. | 0 | below the evidence gate |
| Hydrangea macrocarpa | Hand.-Mazz. | 0 | below the evidence gate |
| Hydrangea mangshanensis | C.F.Wei | 0 | below the evidence gate |
| Hydrangea marunoi | Tagane & S.Fujii | 0 | below the evidence gate |
| Hydrangea mathewsii | Briq. | 0 | below the evidence gate |
| Hydrangea megalocarpa | (Chun) J.M.H.Shaw | 0 | below the evidence gate |
| Hydrangea minamitanii | (H.Ohba) Yahara | 0 | below the evidence gate |
| Hydrangea moellendorffi | Hance | 0 | below the evidence gate |
| Hydrangea mollissima | (Merr.) Y.De Smet & Granados | 0 | below the evidence gate |
| Hydrangea nebulicola | Nevling & Gómez Pompa | 0 | below the evidence gate |
| Hydrangea obtusifolia | (Hu) Y.De Smet & Granados | 0 | below the evidence gate |
| Hydrangea ofeliae | Sodusta & Lumawag | 0 | below the evidence gate |
| Hydrangea platyarguta | Y.De Smet & C.Granados | 0 | below the evidence gate |
| Hydrangea preslii | Briq. | 0 | below the evidence gate |
| Hydrangea robusta | Hook.f. & Thomson | 0 | below the evidence gate |
| Hydrangea sargentiana | Rehder | 0 | below the evidence gate |
| Hydrangea schizomollis | Y.De Smet & Granados | 0 | below the evidence gate |
| Hydrangea sikokiana | Maxim. | 0 | below the evidence gate |
| Hydrangea steyermarkii | Standl. | 0 | below the evidence gate |
| Hydrangea strigosa | Rehder | 0 | below the evidence gate |
| Hydrangea stylosa | Hook.f. & Thomson | 0 | below the evidence gate |
| Hydrangea taiwaniana | Y.C.Liu & F.Y.Lu | 0 | below the evidence gate |
| Hydrangea tarapotensis | Briq. | 0 | below the evidence gate |
| Hydrangea tomentella | (Hand.-Mazz.) Y.De Smet & Granados | 0 | below the evidence gate |
| Hydrangea versicolor | (Fortune) J.M.H.Shaw | 0 | below the evidence gate |
| Hydrangea wallichii | J.M.H.Shaw | 0 | below the evidence gate |
| Hydrangea xanthoneura | Diels | 0 | below the evidence gate |
| Hydrangea yaoshanensis | (Y.C.Wu) Y.De Smet & Granados | 0 | below the evidence gate |
| Hydrangea ytiensis | (J.M.H.Shaw) J.M.H.Shaw | 0 | below the evidence gate |
| Hydrangea yunnanensis | Rehder | 0 | below the evidence gate |
| Hydrangea zhewanensis | P.S.Hsu & X.P.Zhang | 0 | below the evidence gate |
This site is commercial, so it can only publish photographs licensed for commercial use. Roughly three quarters of the photographs on iNaturalist are CC BY-NC, which excludes them. A species needs at least three usable photographs before we will build it a page, because a page with one picture and no traits tells you nothing you could not get from a search result, and generating hundreds of thousands of those is precisely the practice that got the previous version of this site deleted.
So the species above without a link are not errors and they are not omissions. They are real, accepted plants that we cannot yet document to the standard we hold ourselves to, and the count in the photographs column is exactly how far short we fall.