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Arum nigrum

Black Arum

Family AraceaeGenus Arum

A dark maroon spathe standing upright among broad green arrow-shaped leaves, with a garden label behind it
FlowerMichael WolfCC BY-SA 3.0

About the plant

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

Habit
tuberous geophytePlants of the World Online
Flower
Dark maroonRead from the photograph on this page
Native range
Greece, NW. Balkan Pen.GBIF Backbone Taxonomy

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

Sources: Plants of the World Online — Royal Botanic Gardens, Kew; Read from the photograph on this page — Deno's Garden; GBIF Backbone Taxonomy — Global Biodiversity Information Facility.

Worth knowing

  • Black arum, from the Balkans and northern Greece, grows from a large underground tuber that stores food and carries the plant through drought. Its black flowers, a spadix in a large petal-like bract, are its most distinctive feature. Wikipedia: Arum nigrum

This source reports two treatments. Both are shown.

Protocol 1

DerivedN. C. Deno, 1998

Difficulty Moderate Rated by us, not by the source.

Start around September 17, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on September 16, 2026.

  1. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°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

about 6 months from start to step 3. Germination happens during step 3, in 21 days.

100% germination in 7–21 days.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Arum p. 15Public domain
Show the original text
Arum (Araceae). A. nigrum germ. 70D(1/9 in 7th w)-40(2/9 in 4th w) and 40-70D-40(4/4 in 1-3 w).
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Arum p. 15. 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 High Rated by us, not by the source.

Start around December 8, 2026 for a May 3 last frost.

  1. Warm moist stratification

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

    1/9 germinated in this phase.

  2. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

about 3 months from start to step 2. Germination happens during step 2, in 28 days.

22% germination in 28 days.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Arum p. 15Public domain
Show the original text
Arum (Araceae). A. nigrum germ. 70D(1/9 in 7th w)-40(2/9 in 4th w) and 40-70D-40(4/4 in 1-3 w).
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Arum p. 15. 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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