| Hydrangea acuminata Siebold & Zucc. | Hydrangea serrata (Thunb.) Ser. var. serrata | | | Hydrangea acuminataSiebold & Zucc. | Hydrangea serrata(Thunb.) Ser. var.serrata |
| Hydrangea anomala D. Don | | a | | Hydrangea anomalaD. Don | |
| Hydrangea aspera Buch.-Ham. ex D. Don | | a | | Hydrangea asperaBuch.-Ham. ex D. Don | |
| Hydrangea bretschneideri Dippel | | a | | Hydrangea bretschneideriDippel | |
| Hydrangea bretschneideri Dippel var. setchuenensis Rehder | Hydrangea xanthoneura Diels | | i | Hydrangea bretschneideriDippel var.setchuenensis Rehder | Hydrangea xanthoneuraDiels |
| Hydrangea chinensis Maxim. | | a | | Hydrangea chinensisMaxim. | |
| Hydrangea dumicola W. W. Sm. | | a | | Hydrangea dumicolaW. W. Sm. | |
| Hydrangea heteromalla D. Don | | a | | Hydrangea heteromallaD. Don | |
| Hydrangea hirta (Thunb.) Siebold | | a | | Hydrangea hirta(Thunb.) Siebold | |
| Hydrangea integerrima (Hook. & Arn.) Engl. | Hydrangea serratifolia (Hook. & Arn.) F. Phil. | | | Hydrangea integerrima(Hook. & Arn.) Engl. | Hydrangea serratifolia(Hook. & Arn.) F. Phil. |
| Hydrangea integrifolia Hayata | | a | | Hydrangea integrifoliaHayata | |
| Hydrangea involucrata Siebold | | a | | Hydrangea involucrataSiebold | |
| Hydrangea longipes Franch. | | a | | Hydrangea longipesFranch. | |
| Hydrangea macrophylla (Thunb.) Ser. | | a | | Hydrangea macrophylla(Thunb.) Ser. | |
| Hydrangea oblongifolia Blume | Hydrangea aspera Buch.-Ham. ex D. Don | | | Hydrangea oblongifoliaBlume | Hydrangea asperaBuch.-Ham. ex D. Don |
| Hydrangea opuloides (Lam.) K. Koch | Hydrangea macrophylla (Thunb.) Ser. | | | Hydrangea opuloides(Lam.) K. Koch | Hydrangea macrophylla(Thunb.) Ser. |
| Hydrangea opuloides (Lam.) K. Koch var. serrata (Thunb.) Rehder | Hydrangea serrata (Thunb.) Ser. var. serrata | | i | Hydrangea opuloides(Lam.) K. Koch var.serrata (Thunb.) Rehder | Hydrangea serrata(Thunb.) Ser. var.serrata |
| Hydrangea paniculata Siebold | | a | | Hydrangea paniculataSiebold | |
| Hydrangea paniculata Siebold var. intermedia Bois ex Nakai | Hydrangea paniculata Siebold | | i | Hydrangea paniculataSiebold var.intermedia Bois ex Nakai | Hydrangea paniculataSiebold |
| Hydrangea paniculata Siebold var. praecox Rehder | Hydrangea paniculata Siebold | | i | Hydrangea paniculataSiebold var.praecox Rehder | Hydrangea paniculataSiebold |
| Hydrangea petiolaris Siebold & Zucc. | | a | | Hydrangea petiolarisSiebold & Zucc. | |
| Hydrangea robusta Hook. f. & Thomson | | a | | Hydrangea robustaHook. f. & Thomson | |
| Hydrangea rosthornii Diels | Hydrangea robusta Hook. f. & Thomson | | | Hydrangea rosthorniiDiels | Hydrangea robustaHook. f. & Thomson |
| Hydrangea scandens (L. f.) Ser. | | a | | Hydrangea scandens(L. f.) Ser. | |
| Hydrangea scandens (L. f.) Ser. subsp. liukiuensis (Nakai) E. M. McClint. | Hydrangea liukiuensis Nakai | | i | Hydrangea scandens(L. f.) Ser. subsp. liukiuensis (Nakai) E. M. McClint. | Hydrangea liukiuensisNakai |
| Hydrangea serrata (Thunb.) Ser. | | a | | Hydrangea serrata(Thunb.) Ser. | |
| Hydrangea serrata (Thunb.) Ser. f. acuminata (Siebold & Zucc.) E. H. Wilson | Hydrangea serrata (Thunb.) Ser. var. serrata | | i | Hydrangea serrata(Thunb.) Ser. f. acuminata (Siebold & Zucc.) E. H. Wilson | Hydrangea serrata(Thunb.) Ser. var.serrata |
| Hydrangea strigosa Rehder | | a | | Hydrangea strigosaRehder | |
| Hydrangea thunbergii Siebold | Hydrangea serrata (Thunb.) Ser. var. thunbergii (Siebold) H. Ohba | | | Hydrangea thunbergiiSiebold | Hydrangea serrata(Thunb.) Ser. var.thunbergii (Siebold) H. Ohba |
| Hydrangea vestita Wall. | Hydrangea heteromalla D. Don | | | Hydrangea vestitaWall. | Hydrangea heteromallaD. Don |
| Hydrangea xanthoneura Diels | | a | | Hydrangea xanthoneuraDiels | |
| Hydrangea xanthoneura Diels var. setchuenensis (Rehder) Rehder | Hydrangea xanthoneura Diels | | i | Hydrangea xanthoneuraDiels var.setchuenensis (Rehder) Rehder | Hydrangea xanthoneuraDiels |
| Hydrangea xanthoneura Diels var. wilsonii Rehder | Hydrangea xanthoneura Diels | | i | Hydrangea xanthoneuraDiels var.wilsonii Rehder | Hydrangea xanthoneuraDiels |
| Hydrangea yunnanensis Rehder | Hydrangea davidii Franch. | | | Hydrangea yunnanensisRehder | Hydrangea davidiiFranch. |
| Hydrangea macrophylla (Thunb.) Ser. subsp. macrophylla | Hydrangea macrophylla (Thunb.) Ser. | | i | Hydrangea macrophylla(Thunb.) Ser. subsp. macrophylla | Hydrangea macrophylla(Thunb.) Ser. |
| Hydrangea anomala D. Don subsp. petiolaris (Siebold & Zucc.) E. M. McClint. | Hydrangea petiolaris Siebold & Zucc. | | i | Hydrangea anomalaD. Don subsp. petiolaris (Siebold & Zucc.) E. M. McClint. | Hydrangea petiolarisSiebold & Zucc. |
| Hydrangea arborescens L. | | a | | Hydrangea arborescensL. | |
| Hydrangea spp. | | a | | Hydrangea spp. | |
| Hydrangea luteovenosa Koidz. | | a | | Hydrangea luteovenosaKoidz. | |
| Hydrangea liukiuensis Nakai | | a | | Hydrangea liukiuensisNakai | |
| Hydrangea macrophylla (Thunb.) Ser. subsp. serrata (Thunb.) Makino | Hydrangea serrata (Thunb.) Ser. var. serrata | | i | Hydrangea macrophylla(Thunb.) Ser. subsp. serrata (Thunb.) Makino | Hydrangea serrata(Thunb.) Ser. var.serrata |
| Hydrangea anomala D. Don subsp. anomala | Hydrangea anomala D. Don | | i | Hydrangea anomalaD. Don subsp. anomala | Hydrangea anomalaD. Don |
| Hydrangea scandens (L. f.) Ser. subsp. chinensis (Maxim.) E. M. McClint. | Hydrangea chinensis Maxim. | | i | Hydrangea scandens(L. f.) Ser. subsp. chinensis (Maxim.) E. M. McClint. | Hydrangea chinensisMaxim. |
| Hydrangea serratifolia (Hook. & Arn.) F. Phil. | | a | | Hydrangea serratifolia(Hook. & Arn.) F. Phil. | |
| Hydrangea aspera Buch.-Ham. ex D. Don subsp. robusta (Hook. f. & Thomson) E. M. McClint. | Hydrangea robusta Hook. f. & Thomson | | i | Hydrangea asperaBuch.-Ham. ex D. Don subsp. robusta (Hook. f. & Thomson) E. M. McClint. | Hydrangea robustaHook. f. & Thomson |
| Hydrangea aspera Buch.-Ham. ex D. Don subsp. strigosa (Rehder) E. M. McClint. | Hydrangea strigosa Rehder | | i | Hydrangea asperaBuch.-Ham. ex D. Don subsp. strigosa (Rehder) E. M. McClint. | Hydrangea strigosaRehder |
| Hydrangea aspera Buch.-Ham. ex D. Don subsp. aspera | Hydrangea aspera Buch.-Ham. ex D. Don | | i | Hydrangea asperaBuch.-Ham. ex D. Don subsp. aspera | Hydrangea asperaBuch.-Ham. ex D. Don |
| Hydrangea villosa Rehder | Hydrangea aspera Buch.-Ham. ex D. Don | | | Hydrangea villosaRehder | Hydrangea asperaBuch.-Ham. ex D. Don |
| Hydrangea quercifolia W. Bartram | | a | | Hydrangea quercifoliaW. Bartram | |
| Hydrangea aspera Buch.-Ham. ex D. Don subsp. sargentiana (Rehder) E. M. McClint. | Hydrangea sargentiana Rehder | | i | Hydrangea asperaBuch.-Ham. ex D. Don subsp. sargentiana (Rehder) E. M. McClint. | Hydrangea sargentianaRehder |
| Hydrangea sargentiana Rehder | | a | | Hydrangea sargentianaRehder | |
| Hydrangea fulvescens Rehder | Hydrangea longipes Franch. var. fulvescens (Rehder) W. T. Wang ex C. F. Wei | | | Hydrangea fulvescensRehder | Hydrangea longipesFranch. var.fulvescens (Rehder) W. T. Wang ex C. F. Wei |
| Hydrangea arborescens L. subsp. arborescens | Hydrangea arborescens L. | | i | Hydrangea arborescensL. subsp. arborescens | Hydrangea arborescensL. |
| Hydrangea arborescens L. subsp. discolor (Ser. ex DC.) E. M. McClint. | Hydrangea cinerea Small | | i | Hydrangea arborescensL. subsp. discolor (Ser. ex DC.) E. M. McClint. | Hydrangea cinereaSmall |
| Hydrangea arborescens L. var. discolor Ser. ex DC. | Hydrangea cinerea Small | | i | Hydrangea arborescensL. var.discolor Ser. ex DC. | Hydrangea cinereaSmall |
| Hydrangea cinerea Small | | a | | Hydrangea cinereaSmall | |
| Hydrangea arborescens L. subsp. radiata (Walter) E. M. McClint. | Hydrangea radiata Walter | | i | Hydrangea arborescensL. subsp. radiata (Walter) E. M. McClint. | Hydrangea radiataWalter |
| Hydrangea radiata Walter | | a | | Hydrangea radiataWalter | |
| Hydrangea macrophylla (Thunb.) Ser. subsp. stylosa (Hook. f. & Thomson) E. M. McClint. | Hydrangea stylosa Hook. f. & Thomson | | i | Hydrangea macrophylla(Thunb.) Ser. subsp. stylosa (Hook. f. & Thomson) E. M. McClint. | Hydrangea stylosaHook. f. & Thomson |
| Hydrangea stylosa Hook. f. & Thomson | | a | | Hydrangea stylosaHook. f. & Thomson | |
| Hydrangea kwangsiensis Hu | | a | | Hydrangea kwangsiensisHu | |
| Hydrangea macrophylla (Thunb.) Ser. subsp. chungii (Rehder) E. M. McClint. | Hydrangea chungii Rehder | | i | Hydrangea macrophylla(Thunb.) Ser. subsp. chungii (Rehder) E. M. McClint. | Hydrangea chungiiRehder |
| Hydrangea chungii Rehder | | a | | Hydrangea chungiiRehder | |
| Hydrangea hortensia Siebold | Hydrangea macrophylla (Thunb.) Ser. | | | Hydrangea hortensiaSiebold | Hydrangea macrophylla(Thunb.) Ser. |
| Hydrangea seemannii L. Riley | | a | | Hydrangea seemanniiL. Riley | |
| Hydrangea altissima Wall. | Hydrangea anomala D. Don | | | Hydrangea altissimaWall. | Hydrangea anomalaD. Don |
| Hydrangea longipes Franch. var. fulvescens (Rehder) W. T. Wang ex C. F. Wei | | a | i | Hydrangea longipesFranch. var.fulvescens (Rehder) W. T. Wang ex C. F. Wei | |
| Hydrangea longipes Franch. var. longipes | | a | i | Hydrangea longipesFranch. var.longipes | |
| Hydrangea davidii Franch. | | a | | Hydrangea davidiiFranch. | |
| Hydrangea serrata (Thunb.) Ser. var. serrata | | a | i | Hydrangea serrata(Thunb.) Ser. var.serrata | |
| Hydrangea serrata (Thunb.) Ser. var. thunbergii (Siebold) H. Ohba | | a | i | Hydrangea serrata(Thunb.) Ser. var.thunbergii (Siebold) H. Ohba | |
| Hydrangea macrophylla (Thunb.) Ser. subsp. serrata (Thunb.) Makino var. acuminata (Siebold & Zucc.) Makino | Hydrangea serrata (Thunb.) Ser. var. serrata | | i | Hydrangea macrophylla(Thunb.) Ser. subsp. serrata (Thunb.) Makino var.acuminata (Siebold & Zucc.) Makino | Hydrangea serrata(Thunb.) Ser. var.serrata |
| Hydrangea arborescens L. var. arborescens | Hydrangea arborescens L. | | i | Hydrangea arborescensL. var.arborescens | Hydrangea arborescensL. |
| Hydrangea bretschneideri Dippel var. bretschneideri | Hydrangea bretschneideri Dippel | | i | Hydrangea bretschneideriDippel var.bretschneideri | Hydrangea bretschneideriDippel |
| Hydrangea macrophylla (Thunb.) Ser. var. macrophylla | Hydrangea macrophylla (Thunb.) Ser. | | i | Hydrangea macrophylla(Thunb.) Ser. var.macrophylla | Hydrangea macrophylla(Thunb.) Ser. |
| Hydrangea opuloides (Lam.) K. Koch var. opuloides | Hydrangea macrophylla (Thunb.) Ser. | | i | Hydrangea opuloides(Lam.) K. Koch var.opuloides | Hydrangea macrophylla(Thunb.) Ser. |
| Hydrangea paniculata Siebold var. paniculata | Hydrangea paniculata Siebold | | i | Hydrangea paniculataSiebold var.paniculata | Hydrangea paniculataSiebold |
| Hydrangea scandens (L. f.) Ser. subsp. scandens | Hydrangea scandens (L. f.) Ser. | | i | Hydrangea scandens(L. f.) Ser. subsp. scandens | Hydrangea scandens(L. f.) Ser. |
| Hydrangea serrata (Thunb.) Ser. f. serrata | Hydrangea serrata (Thunb.) Ser. | | i | Hydrangea serrata(Thunb.) Ser. f. serrata | Hydrangea serrata(Thunb.) Ser. |
| Hydrangea xanthoneura Diels var. xanthoneura | Hydrangea xanthoneura Diels | | i | Hydrangea xanthoneuraDiels var.xanthoneura | Hydrangea xanthoneuraDiels |
| Hydrangea alternifolia Siebold | | a | | Hydrangea alternifoliaSiebold | |
| Hydrangea ampla (Chun) Y. De Smet & C. Granados | | a | | Hydrangea ampla(Chun) Y. De Smet & C. Granados | |
| Hydrangea barbara (L.) Bernd Schulz | | a | | Hydrangea barbara(L.) Bernd Schulz | |
| Hydrangea bifida (Maxim.) Y. De Smet & C. Granados | | a | | Hydrangea bifida(Maxim.) Y. De Smet & C. Granados | |
| Hydrangea febrifuga (Lour.) Y. De Smet & C. Granados | | a | | Hydrangea febrifuga(Lour.) Y. De Smet & C. Granados | |
| Hydrangea hydrangeoides (Siebold & Zucc.) Bernd Schulz | | a | | Hydrangea hydrangeoides(Siebold & Zucc.) Bernd Schulz | |
| Hydrangea hypoglauca Rehder | | a | | Hydrangea hypoglaucaRehder | |
| Hydrangea platyarguta Y. De Smet & Samain | | a | | Hydrangea platyargutaY. De Smet & Samain | |
| Hydrangea arguta (Gaudich.) Y. De Smet & C. Granados | | a | | Hydrangea arguta(Gaudich.) Y. De Smet & C. Granados | |
| Hydrangea obtusifolia (Hu) Y. De Smet & C. Granados | | a | | Hydrangea obtusifolia(Hu) Y. De Smet & C. Granados | |
| Hydrangea viburnoides (Hook. f. & Thomson) Y. De Smet & C. Granados | | a | | Hydrangea viburnoides(Hook. f. & Thomson) Y. De Smet & C. Granados | |