A hybrid, intermediate in features between its parents T. americana and T. platyphyllos.
Habitat A hybrid found only in cultivation.
USDA Hardiness Zone 3-7
RHS Hardiness Rating H7
Hybrids of Tilia platyphyllos (Broad-leaved Lime) and T. americana (Basswood) are liable to occur whenever both species are grown together in areas with warm summers. The cross was first described in 1862 from a tree in the Vienna Botanic Garden (Pigott 2012). A very vigorous tree of 19m, dbh 233 cm in 2017 was apparently planted as T. × flaccida in 1957 in the Freundschaftsinsel Park, Potsdam, Germany (monumentaltrees.com 2018). Ari Hyvärinen (pers. comm. 2021) reports that he grows T. × flaccida successfully in Oulu in northern Finland
(65.013784817°N, 25.472099070°E), and that it is also grown in Helsinki.
In addition to the cultivar described below, Heinze (2004) showed that trees with hybrid features such as rudimentary staminodes were widespread as younger plantings in Germany; at least some of these had been supplied under the name T. americana ‘Nova’ (q.v.). This might imply that ‘Nova’ belongs here, but does not preclude the possibility that those examples were wrongly named. We have not examined stock of ‘Nova’ for this account. Krüssmann (1984) describes ‘Diversifolia’ as a slender, upright tree with variably dissected leaves.
A broad-crowned tree, the original 20 m tall and generally resembling T. platyphyllos, with light green leaves to 11 cm long and inflorescences with 2–7 flowers. Selected at the Holbaek Park, Denmark in 1995, it is marketed as a hardy street tree for Scandinavia as part of the Norðîc® range (Jablonski & Plietzsch 2014; A-plant 2000 (2017)).