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Inula helenium

Elecampane · Elecampane Inula · Horseheal

Family AsteraceaeGenus Inula

A tall leafy clump crowded with yellow daisies of thin ragged rays, above coarse toothed leaves
The whole plantKareljCC BY-SA 3.0

About the plant

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

The plant

Habit
WildflowerExtension Gardener Plant Toolbox
Habit
perennialPlants of the World Online
Height
2-6 ft0.6-1.8 mExtension Gardener Plant Toolbox
Spread
2-3 ft60-90 cmExtension Gardener Plant Toolbox
Flower
Gold/YellowExtension Gardener Plant Toolbox
Blooms
Fall, SummerExtension Gardener Plant Toolbox
Native range
Albania, Altay, Bulgaria, Greece, Iran, Iraq and elsewhereGBIF Backbone Taxonomy
Hardiness zones
3-7Extension Gardener Plant Toolbox

Growing conditions

Sun
Full sunExtension Gardener Plant Toolbox
Soil
Clay, Loam (Silt)Extension Gardener Plant Toolbox
Soil pH
Acid (<6.0), Neutral (6.0-8.0)Extension Gardener Plant Toolbox
Moisture
Good Drainage, MoistExtension 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

  • Its name helenium comes from Helen of Troy: elecampane was said to have sprung up where her tears fell. It was once called elfwort, and was held to belong to the elves and fairy folk. Wikipedia: Elecampane

Two sources report two treatments between them. Both are shown.

Protocol 1

DerivedN. C. Deno, 1998

Difficulty High Rated by us, not by the source.

Start around February 23, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on February 22, 2025.

  1. Dry storage

    Duration: 730 daysTemperature: 70°F 21°C

  2. Warm moist stratification

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

  3. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  4. Warm moist stratification

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

    1/17 germinated in this phase.

Steps after step 2 run on after germination.

about 2 years from start to step 2. Germination happens during step 2, in 42 days.

18% germination in 14–42 days.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Inula p. 39Public domain
Show the original text
Inula (Asteraceae). I. helenium DS 2 y germ. 70D(3/17 in 2-6 w)-40- 70D(1/17) and seeds DS 3 y germ. 70D(T/16 in 4th w).
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Inula p. 39. 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, 1996

Difficulty Moderate Rated by us, not by the source.

Start around March 27, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on March 26, 2026.

  1. Dry storage

    Duration: 180–365 daysTemperature: 70°F 21°C

  2. Sow and cover

    Temperature: 70°F 21°C Light: light

about 12 months from start to sowing. Then 10 days to germinate.

50% germination in 5–10 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Inula p. 49Public domain
Show the original text
Inula (Asteraceae). I. helenium germ. 70L(50% in 5-10 d) and 70D(none) using seeds DS either 6 m or 1 y.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Inula p. 49. 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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