Deno’s Garden

Dodecatheon jeffreyanum

Genus Dodecatheon

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 October 2, 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 6 months from start to sowing. Then 5 days to germinate.

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, 2026 — a date the source gives, not one counted back from a May 3 last frost.

  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.

This source doesn't state how long.

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 September 30, 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 6 months from start to sowing. Then 7 days to germinate.

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 December 15, 2026 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.

about 3 months from start to sowing. Germination 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.