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Datura stramonium

Jimsonweed · Common Thorn-apple · Jamestown Weed

Family SolanaceaeGenus Datura

A white trumpet flower with a purple throat among large, jagged-edged green leaves
FlowerTim KirstenCC0
A color plate of a white trumpet flower on a stem of jagged leaves, with the spiny capsule whole, in cross-section, split open over its seeds, and single seeds drawn enlarged
IllustrationFranz Eugen Köhler, Köhler's Medizinal-PflanzenPublic domain

About the plant

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

Safety

Toxicity
Poisonous to cattle, humans, horses, goats. Flowers, leaves, seeds. Stated for Datura spp.Plants Poisonous to Livestock
Toxicity
High severity. All parts. Tropane alkaloids scopolamine, hyoscyamine, and atropine.Extension Gardener Plant Toolbox

The plant

Habit
Annual, Herbaceous PerennialExtension Gardener Plant Toolbox
Habit
annualPlants of the World Online
Height
1-4 ft0.3-1.2 mExtension Gardener Plant Toolbox
Spread
1-4 ft0.3-1.2 mExtension Gardener Plant Toolbox
Flower
Purple/Lavender, WhiteExtension Gardener Plant Toolbox
Blooms
SummerExtension Gardener Plant Toolbox
Hardiness zones
7-9Extension Gardener Plant Toolbox
Note
Introduced across the US and Canada; not native to North America.PLANTS Database

Growing conditions

Sun
Full sun; Partial ShadeExtension Gardener Plant Toolbox
Soil
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, 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; Plants Poisonous to Livestock — Cornell University Department of Animal Science; PLANTS Database — USDA NRCS.

Worth knowing

  • Datura comes from the Hindi dhatūra. Every part contains dangerous levels of atropine, hyoscyamine and scopolamine. Wikipedia: Datura stramonium

This source reports 6 treatments. All are shown.

Protocol 1

DerivedN. C. Deno, 1993

Difficulty Low 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. Dry storage

    Duration: 180 daysTemperature: 70°F 21°C

  2. Sow on the surface — do not cover

    Temperature: 70°F 21°C Light: light

about 6 months from start to sowing. Germination time not stated; 21 days assumed.

100% germination.

Six months of dry storage at 70 raises it from 27% to 100%.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, DaturaPublic domain
Show the original text
Datura (Solanaceae). D. stramonium germ. 100% in 70L if the seed had been DS 6m at 70 whereas fresh seed germ. only 70L(27% in 8-10 d). There is some germination in the dark as shown by 70D(25% in 3-7 d) for seed DS 6 m at 70 and 70D(15% in 5-8 d) for seed collected in November. Germination failed in outdoor treatment. Germination was only 5% over two cycles when sown at 40.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Datura. 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, 1993

Difficulty Moderate Rated by us, not by the source.

Start around March 26, 2027 for a May 3 last frost.

  1. Sow on the surface — do not cover

    Temperature: 70°F 21°C Light: light

No stated waiting before sowing. Then 10 days to germinate.

27% germination in 8–10 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, DaturaPublic domain
Show the original text
Datura (Solanaceae). D. stramonium germ. 100% in 70L if the seed had been DS 6m at 70 whereas fresh seed germ. only 70L(27% in 8-10 d). There is some germination in the dark as shown by 70D(25% in 3-7 d) for seed DS 6 m at 70 and 70D(15% in 5-8 d) for seed collected in November. Germination failed in outdoor treatment. Germination was only 5% over two cycles when sown at 40.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Datura. 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, 1993

Difficulty Moderate Rated by us, not by the source.

Start around October 1, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on September 30, 2026.

  1. Dry storage

    Duration: 180 daysTemperature: 70°F 21°C

  2. Sow and cover

    Temperature: 70°F 21°C Light: dark

about 6 months from start to sowing. Then 7 days to germinate.

25% germination in 3–7 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, DaturaPublic domain
Show the original text
Datura (Solanaceae). D. stramonium germ. 100% in 70L if the seed had been DS 6m at 70 whereas fresh seed germ. only 70L(27% in 8-10 d). There is some germination in the dark as shown by 70D(25% in 3-7 d) for seed DS 6 m at 70 and 70D(15% in 5-8 d) for seed collected in November. Germination failed in outdoor treatment. Germination was only 5% over two cycles when sown at 40.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Datura. 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, 1993

Difficulty Moderate Rated by us, not by the source.

Start around March 28, 2027 for a May 3 last frost.

  1. Sow and cover

    Temperature: 70°F 21°C Light: dark

No stated waiting before sowing. Then 8 days to germinate.

15% germination in 5–8 days.

Seed collected in November.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, DaturaPublic domain
Show the original text
Datura (Solanaceae). D. stramonium germ. 100% in 70L if the seed had been DS 6m at 70 whereas fresh seed germ. only 70L(27% in 8-10 d). There is some germination in the dark as shown by 70D(25% in 3-7 d) for seed DS 6 m at 70 and 70D(15% in 5-8 d) for seed collected in November. Germination failed in outdoor treatment. Germination was only 5% over two cycles when sown at 40.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Datura. 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, 1993

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

  1. Cold moist stratification

    Temperature: 40°F 4°C

    Only 5% over two cycles.

Germination happens during step 1; time not stated, 21 days assumed.

5% germination.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, DaturaPublic domain
Show the original text
Datura (Solanaceae). D. stramonium germ. 100% in 70L if the seed had been DS 6m at 70 whereas fresh seed germ. only 70L(27% in 8-10 d). There is some germination in the dark as shown by 70D(25% in 3-7 d) for seed DS 6 m at 70 and 70D(15% in 5-8 d) for seed collected in November. Germination failed in outdoor treatment. Germination was only 5% over two cycles when sown at 40.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Datura. Quoted exactly. Every value on this card comes from this record; the step names come from a fixed list.

Protocol 6

DerivedN. C. Deno, 1993

  1. Sow outdoors and leave it

    Germination failed.

No stated waiting before sowing.

0% germination.

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

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, DaturaPublic domain
Show the original text
Datura (Solanaceae). D. stramonium germ. 100% in 70L if the seed had been DS 6m at 70 whereas fresh seed germ. only 70L(27% in 8-10 d). There is some germination in the dark as shown by 70D(25% in 3-7 d) for seed DS 6 m at 70 and 70D(15% in 5-8 d) for seed collected in November. Germination failed in outdoor treatment. Germination was only 5% over two cycles when sown at 40.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Datura. 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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