Fennel
Foeniculum vulgare
A Mediterranean-native culinary herb grown for its anise-scented feathery foliage and seeds, both harvested for the kitchen. Upright branching stems rise 4 to 6 feet and carry flattened compound umbels of tiny yellow flowers in early summer, followed by aromatic seeds. The showy flowers draw butterflies and the foliage is a larval host for swallowtail caterpillars - but fennel self-seeds freely and has naturalized across North America, so spent flowering stems are best cut before seed sets.
Climate fit: moderate (55/100)
Edible
Pollinator
Structure
Light
Full sun
Water
Moderate water
Mature size
4-6 ft tall · 18" apart
Hardy in zones
4a-9b
very cold to frosty winters
AHS heat range
4-11
Plant range authored in AHS heat-zone terms.
Native in Illinois
No
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A documented larval host for the Black swallowtail and 1 other species - caterpillars feed on its foliage before becoming the next generation.
Cold hardiness
These values are location-based: this location's current hardiness is the baseline, and the 2050 value is a projected future climate for this same location.
Now
Zone 6b
Plotwright
USDA Zone 6b
-5°F to 0°F
Well-suited
Zone 7a
Plotwright
0°F to 5°F
Well-suited
In plain terms: This location has cold winters. Its winters are projected to keep warming through 2050.
✓
Well-suited today and still thriving in 2050.
Heat tolerance
Heat tolerance values are location-based too: heat days today are observed at this site, and the 2050 value projects this same location under a future climate.
Loading AHS heat-zone data for this location...
Where this plant fits
Suitable across 42 ecoregions - 38 climate-resilient through 2070 · 1 suited today · 3 newly possible by 2070. Best matches first.
Similar plants
Browse lateral options with similar roles, light needs, size, or native-range overlap; these are not filtered for a better climate fit.
Educator packet
Plant packet
Fennel educator packet
A Mediterranean-native culinary herb grown for its anise-scented feathery foliage and seeds, both harvested for the kitchen. Upright branching stems rise 4 to 6 feet and carry flattened compound umbels of tiny yellow flowers in early summer, followed by aromatic seeds. The showy flowers draw butterflies and the foliage is a larval host for swallowtail caterpillars - but fennel self-seeds freely and has naturalized across North America, so spent flowering stems are best cut before seed sets.
Scientific name
Foeniculum vulgare
Plant type
herb
Hardiness
4a-9b
Light
full-sun
Moisture
moderate
Spacing
18 inches
Classroom prompts
- Which plant traits are observations, and which are care recommendations?
- How would this plant fit change if the garden location moved warmer, colder, wetter, or drier?
- Which source-backed facts would you cite in a lesson handout?
Use the Sources & citations section below for page citation styles and the field-level source list.
Sources & citations
Cite this page
For lesson plans, articles, or research that uses this page. Use the source cards below to explore the references that informed this record.
Plotwright. (2026, May 17). Fennel (Foeniculum vulgare). Retrieved 2026, August 20, from https://plotwright.com/plants/foeniculum-vulgare
Sources used for this record
This record is compiled from the sources below.





