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Dracocephalum tanguticum

Dragonhead

Family LamiaceaeGenus Dracocephalum

A short spike of deep violet-blue two-lipped flowers on a stem with narrow leaves, in dry woodland
FlowerPictured: Dracocephalum ruyschiana, a relativeRoman A. Lagazyuk (Роман А. Лагазюк)CC0

About the plant

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

Habit
perennialPlants of the World Online
Flower
Purple-blue, dark purpleFlora of China
Native range
China North-Central, China South-Central, East Himalaya, Nepal, Qinghai, Tibet and elsewhereGBIF 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; Flora of China — Wu Zhengyi, Peter H. Raven and Hong Deyuan (eds.); GBIF Backbone Taxonomy — Global Biodiversity Information Facility.

This source reports 4 treatments. All are shown.

Protocol 1

DerivedN. C. Deno, 1996

Difficulty High Rated by us, not by the source.

Start around March 14, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on March 13, 2026.

  1. Gibberellic acid soak

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    1/5 germinated in this phase.

  3. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  4. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

  5. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  6. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

about 12 months from start to step 6. Germination happens during step 6, in 28 days.

60% germination in 28 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Dracocephalum p. 39Public domain
Show the original text
Dracocephalum (Lamiaceae). D. tanguticum germ. 70 GA-3(1/5 in 9th w)- 40-70-40-70(3/5 in 4th w), 70L-40(2/5)-70(1/5)-40, 70D-40-70D(1/6)-40(1/6), and none in 40-70D-40-70D-40. No clear pattern emerges from these results except that germination is extended.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Dracocephalum 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 High Rated by us, not by the source.

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

  1. Warm moist stratification

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

  2. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  3. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    1/5 germinated in this phase.

  4. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

Steps after step 2 run on after germination.

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

40% germination.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Dracocephalum p. 39Public domain
Show the original text
Dracocephalum (Lamiaceae). D. tanguticum germ. 70 GA-3(1/5 in 9th w)- 40-70-40-70(3/5 in 4th w), 70L-40(2/5)-70(1/5)-40, 70D-40-70D(1/6)-40(1/6), and none in 40-70D-40-70D-40. No clear pattern emerges from these results except that germination is extended.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Dracocephalum 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 3

DerivedN. C. Deno, 1996

Difficulty High 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. Warm moist stratification

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

  2. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  3. Warm moist stratification

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

  4. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

    1/6 germinated in this phase.

Steps after step 3 run on after germination.

about 6 months from start to step 3. Germination happens during step 3; time not stated, 21 days assumed.

17% germination.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Dracocephalum p. 39Public domain
Show the original text
Dracocephalum (Lamiaceae). D. tanguticum germ. 70 GA-3(1/5 in 9th w)- 40-70-40-70(3/5 in 4th w), 70L-40(2/5)-70(1/5)-40, 70D-40-70D(1/6)-40(1/6), and none in 40-70D-40-70D-40. No clear pattern emerges from these results except that germination is extended.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Dracocephalum 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 4

DerivedN. C. Deno, 1996

  1. Cold moist stratification

    Temperature: 40°F 4°C

Germination happens during step 1.

0% germination.

Nothing germinated at 40.

This source doesn't state how long step 1 lasts.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Dracocephalum p. 39Public domain
Show the original text
Dracocephalum (Lamiaceae). D. tanguticum germ. 70 GA-3(1/5 in 9th w)- 40-70-40-70(3/5 in 4th w), 70L-40(2/5)-70(1/5)-40, 70D-40-70D(1/6)-40(1/6), and none in 40-70D-40-70D-40. No clear pattern emerges from these results except that germination is extended.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Dracocephalum p. 39. Quoted exactly. Every value on this card comes from this record; 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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