Variety traits
Hydrangea macrophylla (Thunb.) Ser.
For Hydrangea macrophylla, winter hardiness is determined by the ability of flower buds formed on the previous year's shoots to withstand low temperatures without damage. The primary criterion for assessment is the preservation of shoots and the flowering potential in the following season.
In the reference 187 varieties crop Bigleaf hydrangea, where this is mentioned in the description.
For Hydrangea macrophylla, the critical parameter is the temperature threshold for damage to generative buds. In traditional varieties, these can be damaged at temperatures around –5 °C, whereas modern series are capable of withstanding up to –23…–29 °C. Winter hardiness assessment includes an analysis of the percentage of overwintered shoots, bud break dynamics, and biochemical markers of adaptation, such as the level of catalase enzymatic activity and cell sap acidity.
Winter hardiness directly determines the cultivation technology and flowering pattern of the crop. In ordinary varieties, freezing of the aerial part leads to a complete absence of flowering, which necessitates mandatory protection or transition to container cultivation. In remontant varieties capable of forming buds on current-year shoots, high winter hardiness primarily influences the timing and abundance of flowering, allowing the plant to recover even in the event of partial loss of the previous year's shoots.
General information about the subject — on the page Winter hardiness.
Selection based on the description text, not on official evaluation: these data are absent from registers. For specific variety details, please refer to its profile.
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
LAKELAND HORTICULTURAL SOCIETY
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Kolster Holding B.V.^^^Horteve Breeding B.V.
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
TIMOTHY D WOOD
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Marie-France Doll
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Kwekerij Sidaco B.V.
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Horteve Breeding B.V., Kolster Holding B.V.
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Lendert De Vos
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Frauke Engel
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Joseph Gray
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Kwekerij Sidaco B.V.
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Hydrangea Breeders Association B.V.
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Joseph Gray
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Information regarding the breeder received in the contribution to CPVO :Rampp
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Blooming Creations International B.V.
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Information regarding the breeder received in the contribution to CPVO :Mouillère L.
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Information regarding the breeder received in the contribution to CPVO :Lemoine
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Yasuhiro Takahashi
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
SNOWFLAKE NURSERY (US)
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Hydrangea Breeders Association B.V.
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Yasuhiro Takahashi
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Frauke Engel
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Information regarding the breeder received in the contribution to CPVO :Monrovia Nursery
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Toyokazu Ichie
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Information regarding the breeder received in the contribution to CPVO :Wädenswil