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Foeniculum vulgare

Fennel · Sweet Fennel · Aniseed-weed

Family ApiaceaeGenus Foeniculum

Fine thread-like blue-green foliage branching from smooth upright stems
LeafRyan HodnettCC BY-SA 4.0

About the plant

What it is and where it grows — not part of any germination protocol.

The plant

Habit
Herb, Herbaceous PerennialExtension Gardener Plant Toolbox
Habit
perennialPlants of the World Online
Height
4-6 ft1.2-1.8 mExtension Gardener Plant Toolbox
Spread
1.5-3.2 ft45-100 cmExtension Gardener Plant Toolbox
Flower
Gold/YellowExtension Gardener Plant Toolbox
Blooms
SummerExtension Gardener Plant Toolbox
Native range
Afghanistan, Albania, Algeria, Baleares, Bulgaria, Corse and elsewhereGBIF Backbone Taxonomy
Hardiness zones
4-9Extension Gardener Plant Toolbox

Growing conditions

Sun
Full sunExtension Gardener Plant Toolbox
Soil
Clay, High Organic Matter, Loam (Silt), SandExtension Gardener Plant Toolbox
Soil pH
Acid (<6.0), Alkaline (>8.0), Neutral (6.0-8.0)Extension Gardener Plant Toolbox
Moisture
Good Drainage, Moist, Occasionally DryExtension Gardener Plant Toolbox

Toxicity is noted only where a source states it. No note here is not a finding of safety.

Sources: Extension Gardener Plant Toolbox — NC State Extension; Plants of the World Online — Royal Botanic Gardens, Kew; GBIF Backbone Taxonomy — Global Biodiversity Information Facility.

Worth knowing

  • Fennel comes through Old French from the Latin faeniculum, a diminutive of faenum, hay. Along with anise, it is one of the main ingredients of absinthe. Wikipedia: Fennel
  • Its aniseed or licorice flavor comes from anethole, which is also found in anise and star anise. Wikipedia: Fennel

Two sources report 6 treatments between them. All are shown.

Protocol 1

DerivedN. C. Deno, 1998

Difficulty Very high Rated by us, not by the source.

Start around March 16, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on March 16, 2023.

  1. Dry storage

    Duration: 1460 daysTemperature: 70°F 21°C

  2. Sow and cover

    Temperature: 70°F 21°C Light: light

about 4 years from start to sowing. Then 21 days to germinate.

9% germination in 21 days.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Foeniculum p. 34Public domain
Show the original text
Foeniculum (Apiaceae). F. vulgare DS 4 y germ. 70L(9% in 3rd w) and 70D(1%). The light requirement is still present (1st Suppl.), but the percent germination is much reduced. ^ *
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Foeniculum p. 34. Quoted exactly. Every value on this card comes from this record, except the difficulty rating, which is ours; the step names come from a fixed list.

Protocol 2

DerivedN. C. Deno, 1998

Difficulty Very high Rated by us, not by the source.

Start around March 16, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on March 16, 2023.

  1. Dry storage

    Duration: 1460 daysTemperature: 70°F 21°C

  2. Sow and cover

    Temperature: 70°F 21°C Light: dark

about 4 years from start to sowing. Germination time not stated; 21 days assumed.

1% germination.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Foeniculum p. 34Public domain
Show the original text
Foeniculum (Apiaceae). F. vulgare DS 4 y germ. 70L(9% in 3rd w) and 70D(1%). The light requirement is still present (1st Suppl.), but the percent germination is much reduced. ^ *
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Foeniculum p. 34. Quoted exactly. Every value on this card comes from this record, except the difficulty rating, which is ours; the step names come from a fixed list.

Protocol 3

DerivedN. C. Deno, 1996

Difficulty Low Rated by us, not by the source.

Start around March 27, 2027 for a May 3 last frost.

  1. Sow and cover

    Temperature: 70°F 21°C Light: light

No stated waiting before sowing. Then 9 days to germinate.

100% germination in 9 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Foeniculum p. 43Public domain
Show the original text
Foeniculum (Apiaceae). F. vulgare germ. 70 GA-3(82% in 7-11 d), 70L(100% on 9th d), 70D(45% in 3rd w), and 40(10%)-70D(25%). RC reported that it germ. at 70, but it is evident that light and GA-3 cause higher percent germination.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Foeniculum p. 43. Quoted exactly. Every value on this card comes from this record, except the difficulty rating, which is ours; the step names come from a fixed list.

Protocol 4

DerivedN. C. Deno, 1996

Difficulty Low Rated by us, not by the source.

Start around March 25, 2027 for a May 3 last frost.

  1. Gibberellic acid soak

  2. Sow and cover

    Temperature: 70°F 21°C

No stated waiting before sowing. Then 11 days to germinate.

82% germination in 7–11 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Foeniculum p. 43Public domain
Show the original text
Foeniculum (Apiaceae). F. vulgare germ. 70 GA-3(82% in 7-11 d), 70L(100% on 9th d), 70D(45% in 3rd w), and 40(10%)-70D(25%). RC reported that it germ. at 70, but it is evident that light and GA-3 cause higher percent germination.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Foeniculum p. 43. Quoted exactly. Every value on this card comes from this record, except the difficulty rating, which is ours; the step names come from a fixed list.

Protocol 5

DerivedN. C. Deno, 1996

Difficulty Moderate Rated by us, not by the source.

Start around March 15, 2027 for a May 3 last frost.

  1. Sow and cover

    Temperature: 70°F 21°C Light: dark

No stated waiting before sowing. Then 21 days to germinate.

45% germination in 21 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Foeniculum p. 43Public domain
Show the original text
Foeniculum (Apiaceae). F. vulgare germ. 70 GA-3(82% in 7-11 d), 70L(100% on 9th d), 70D(45% in 3rd w), and 40(10%)-70D(25%). RC reported that it germ. at 70, but it is evident that light and GA-3 cause higher percent germination.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Foeniculum p. 43. Quoted exactly. Every value on this card comes from this record, except the difficulty rating, which is ours; the step names come from a fixed list.

Protocol 6

DerivedN. C. Deno, 1996

Difficulty High Rated by us, not by the source.

Start around December 15, 2026 for a May 3 last frost.

  1. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

    10 germinated in this phase.

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C Light: dark

about 3 months from start to step 2. Germination happens during step 2; time not stated, 21 days assumed.

25% germination.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Foeniculum p. 43Public domain
Show the original text
Foeniculum (Apiaceae). F. vulgare germ. 70 GA-3(82% in 7-11 d), 70L(100% on 9th d), 70D(45% in 3rd w), and 40(10%)-70D(25%). RC reported that it germ. at 70, but it is evident that light and GA-3 cause higher percent germination.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Foeniculum p. 43. Quoted exactly. Every value on this card comes from this record, except the difficulty rating, which is ours; the step names come from a fixed list.

How each step is done, in Deno’s words, and what Verified and Derived mean.

Germination trials

Readers’ own records of sowing this species, published after review. Share your trial · All trials

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