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Rhodiola integrifolia

Entire-leaved Rosewort · Entire-leaved Stonecrop · King's Crown · Ledge Stonecrop

Family CrassulaceaeGenus Rhodiola

Dense heads of dark red flowers on upright stems clothed in fleshy blue-green leaves, growing between granite boulders.
FlowerJerryFriedmanCC BY-SA 3.0

About the plant

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

Habit
succulent perennialPlants of the World Online
Habit
Perennial, Forb/herbPLANTS Database
Flower
Dark redFlora of North America
Native range
Alaska, Canada, lower 48 statesPLANTS Database

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; PLANTS Database — USDA NRCS; Flora of North America — Flora of North America Editorial Committee.

Worth knowing

  • One subspecies of ledge stonecrop, leedyi, is a relict of the ice age, surviving on bare cliffs in Minnesota and upstate New York that are kept cold by air blowing out of caves. In 2024 a Cornell University team established a new population in a nearby canyon. Wikipedia: Rhodiola integrifolia

This source reports three treatments. All are shown.

Protocol 1

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: light

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

30% germination in 4–8 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Rhodiola p. 204Public domain
Show the original text
Rhodiola (Crassulaceae). A. atropurpurea germ. 70L(30% in 4-8 d), 70D(10%), and 40-70D(1%).
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Rhodiola p. 204. 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 High 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. Germination time not stated; 21 days assumed.

10% germination.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Rhodiola p. 204Public domain
Show the original text
Rhodiola (Crassulaceae). A. atropurpurea germ. 70L(30% in 4-8 d), 70D(10%), and 40-70D(1%).
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Rhodiola p. 204. 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 Very 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

  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.

1% germination.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Rhodiola p. 204Public domain
Show the original text
Rhodiola (Crassulaceae). A. atropurpurea germ. 70L(30% in 4-8 d), 70D(10%), and 40-70D(1%).
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Rhodiola p. 204. 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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