Bronze fennel (Foeniculum vulgare ‘Purpureum’) – hardiness zones in USDA, RHS, Canadian & Australian systems

Tall perennial fennel with the same anise-scented foliage and yellow umbel flowers as the green form, but with smoky purple-bronze new growth.

Hardiness ratings

Bronze fennel hardiness across the four zone systems
System	Rating	Temperature range	How to read it
USDA hardiness zone	Zone 4–9	−34.4 °C to −1.1 °C	Plant tolerates down to this zone
RHS hardiness rating	H6	−20 °C to −15 °C	Plant needs at least this level of cold tolerance
Canadian plant hardiness zone	Zone 4–8	−29 °C to −1 °C	Plant tolerates down to this zone
Australian (ANBG) zone	Zone 1–6	−15 °C to 15 °C	Plant tolerates down to this zone

Larval food plant for swallowtail butterfly caterpillars and host to numerous parasitic wasp species
Ornamental purple-bronze foliage works as a structural plant in the back of a border
This entry covers the ornamental companion-plant cultivar, distinct from the culinary herb fennel already in the database
Drought tolerant and self-seeds freely