A garden hybrid, intermediate in features between its parents.
USDA Hardiness Zone 4
RHS Hardiness Rating H7
The hybrid between F. ovata and F. suspensa was one of many crosses experimentally made by Bolesław Suszka in Poland between 1952 and 1955, and was part of the first group to be selected for further breeding (Suszka 1959). The hybrid was formally described by Włodzimierz Seneta in 1965 from a plant then growing at the Warsaw University of Life Sciences’ park at Ursynów.
The same cross was independently made by Arthur Simmonds VMH, in his garden in Clandon, Surrey, and was being distributed by the Hilliers Nurseries by the 1970s under the name Forsythia ‘Volunteer’. ‘Volunteer’ made a vigorous plant with dark brown shoots and densely clustered deep yellow flowers (Edwards & Marshall 2019).
It is not known whether this cross is still cultivated in any form. F. × variabilis appears in the species list for the Charles University Botanical Garden in Prague, hosted by florius.cz (Florius 2021), but not all of the taxa on this list are necessarily represented by living plants.