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Primula jeffreyi

Sierra Shooting Star · Jeffrey's Shooting Star · Tall Mountain Shooting Star

Family PrimulaceaeGenus Primula

Also published as Dodecatheon jeffreyanum. You are in the right place.

A clump of long upright leaves with a tall stalk of pink-purple shooting-star flowers, their petals swept back
The whole plantDcrjsrCC BY 3.0

About the plant

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

Habit
perennialPlants of the World Online
Flower
Pink-purpleRead from the photograph on this page

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.

This source reports 5 treatments. All are shown.

Protocol 1

DerivedN. C. Deno, 1993

Difficulty Moderate Rated by us, not by the source.

Start around December 31, 2026 for a May 3 last frost.

  1. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

    4 germinated in this phase.

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

about 3 months from start to step 2. Germination happens during step 2, in 5 days.

90% germination in 1–5 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Dodecatheon p. 134Public domain
Show the original text
Dodecatheon (Primulaceae). D. jeffreyi germ. much better in a 40-70 pattern than when sown at 70 as shown by 40(4%)-70(90% in 1-5 d) and 70(21%)-40-70(2%). Seed sown on November 1 in outdoor treatment germ. 78% in February and March. This outdoor treatment was in effect similar to direct sowing at 40. Germination was nearly as good with seed IDS m at 70 or 40 as shown by 40(12%)-70(65% in 1-7 d) and 70(12%). As with fresh seed germination was lower and more extended when the DS seed was sown at 70.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Dodecatheon p. 134. 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 Low Rated by us, not by the source.

Sow around November 1, 2027 — a date the source gives, not one counted back from a May 3 last frost. Too late for spring 2027 — that needed starting on November 1, 2026.

  1. Sow outdoors and leave it

    Sown outdoors in November 1; up in February and March.

No stated waiting before sowing. Then 90 days to germinate.

78% germination in 90 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Dodecatheon p. 134Public domain
Show the original text
Dodecatheon (Primulaceae). D. jeffreyi germ. much better in a 40-70 pattern than when sown at 70 as shown by 40(4%)-70(90% in 1-5 d) and 70(21%)-40-70(2%). Seed sown on November 1 in outdoor treatment germ. 78% in February and March. This outdoor treatment was in effect similar to direct sowing at 40. Germination was nearly as good with seed IDS m at 70 or 40 as shown by 40(12%)-70(65% in 1-7 d) and 70(12%). As with fresh seed germination was lower and more extended when the DS seed was sown at 70.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Dodecatheon p. 134. 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 December 29, 2026 for a May 3 last frost.

  1. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

    12 germinated in this phase.

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

about 3 months from start to step 2. Germination happens during step 2, in 7 days.

65% germination in 1–7 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Dodecatheon p. 134Public domain
Show the original text
Dodecatheon (Primulaceae). D. jeffreyi germ. much better in a 40-70 pattern than when sown at 70 as shown by 40(4%)-70(90% in 1-5 d) and 70(21%)-40-70(2%). Seed sown on November 1 in outdoor treatment germ. 78% in February and March. This outdoor treatment was in effect similar to direct sowing at 40. Germination was nearly as good with seed IDS m at 70 or 40 as shown by 40(12%)-70(65% in 1-7 d) and 70(12%). As with fresh seed germination was lower and more extended when the DS seed was sown at 70.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Dodecatheon p. 134. 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 High Rated by us, not by the source.

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

  1. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

  2. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  3. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    2 germinated in this phase.

Steps after step 1 run on after germination.

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

21% germination.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Dodecatheon p. 134Public domain
Show the original text
Dodecatheon (Primulaceae). D. jeffreyi germ. much better in a 40-70 pattern than when sown at 70 as shown by 40(4%)-70(90% in 1-5 d) and 70(21%)-40-70(2%). Seed sown on November 1 in outdoor treatment germ. 78% in February and March. This outdoor treatment was in effect similar to direct sowing at 40. Germination was nearly as good with seed IDS m at 70 or 40 as shown by 40(12%)-70(65% in 1-7 d) and 70(12%). As with fresh seed germination was lower and more extended when the DS seed was sown at 70.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Dodecatheon p. 134. 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

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

No stated waiting before sowing. Germination time not stated; 21 days assumed.

12% germination.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Dodecatheon p. 134Public domain
Show the original text
Dodecatheon (Primulaceae). D. jeffreyi germ. much better in a 40-70 pattern than when sown at 70 as shown by 40(4%)-70(90% in 1-5 d) and 70(21%)-40-70(2%). Seed sown on November 1 in outdoor treatment germ. 78% in February and March. This outdoor treatment was in effect similar to direct sowing at 40. Germination was nearly as good with seed IDS m at 70 or 40 as shown by 40(12%)-70(65% in 1-7 d) and 70(12%). As with fresh seed germination was lower and more extended when the DS seed was sown at 70.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Dodecatheon p. 134. 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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