Deno’s GardenMy Garden

Asclepias cryptoceras

Davis' Milkweed · Humboldt Mountains Milkweed · Humboldt Milkweed · Pallid Milkweed

Family ApocynaceaeGenus Asclepias

Clusters of cream flowers with deep pink centers among broad blue-green oval leaves lying flat on bare soil
FlowerUnknown authorUnknown authorPublic domain

About the plant

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

Habit
perennialPlants of the World Online
Habit
Perennial, Forb/herbPLANTS Database
Flower
Pale green, yellowish greenFlora of North America
Native range
Native to the 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

  • Jewel milkweed, also called cow-cabbage, grows low against the ground in dry places across the Great Basin, with thick, round to heart-shaped leaves. Wikipedia: Asclepias cryptoceras

This source reports 7 treatments. All are shown.

Protocol 1

DerivedN. C. Deno, 1996

Difficulty Low Rated by us, not by the source.

  1. Dry storage

    Duration: 90 daysTemperature: 70°F 21°C

  2. Sow outdoors and leave it

    Up in April.

about 3 months from start to sowing.

100% germination.

This source doesn't state how long step 2 lasts.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Asclepias p. 23Public domain
Show the original text
Asclepias (Asclepiadaceae). A. cryptoceras germ. OT{5/8 in April), 70D(4/8 in 3rd w); and 40-70(6/7 in 1-3 d) using fresh seed. A second sample DS 3 m germ. OT(6/6 in April), 40-70(5/7 in 1-4 w), and 70-40-70-40-70(2/6 on 4th d), but after DS 6 m, it germ. 40-70(1/6 on 2nd d, rest rotted) and 70(all rotted) indicating that nearly all had died after 6 m DS.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Asclepias p. 23. 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 Moderate Rated by us, not by the source.

Start around January 2, 2027 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

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

86% germination in 1–3 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Asclepias p. 23Public domain
Show the original text
Asclepias (Asclepiadaceae). A. cryptoceras germ. OT{5/8 in April), 70D(4/8 in 3rd w); and 40-70(6/7 in 1-3 d) using fresh seed. A second sample DS 3 m germ. OT(6/6 in April), 40-70(5/7 in 1-4 w), and 70-40-70-40-70(2/6 on 4th d), but after DS 6 m, it germ. 40-70(1/6 on 2nd d, rest rotted) and 70(all rotted) indicating that nearly all had died after 6 m DS.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Asclepias p. 23. 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 Moderate Rated by us, not by the source.

Start around September 10, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on September 9, 2026.

  1. Dry storage

    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

about 6 months from start to step 3. Germination happens during step 3, in 28 days.

71% germination in 7–28 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Asclepias p. 23Public domain
Show the original text
Asclepias (Asclepiadaceae). A. cryptoceras germ. OT{5/8 in April), 70D(4/8 in 3rd w); and 40-70(6/7 in 1-3 d) using fresh seed. A second sample DS 3 m germ. OT(6/6 in April), 40-70(5/7 in 1-4 w), and 70-40-70-40-70(2/6 on 4th d), but after DS 6 m, it germ. 40-70(1/6 on 2nd d, rest rotted) and 70(all rotted) indicating that nearly all had died after 6 m DS.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Asclepias p. 23. 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

Difficulty Moderate Rated by us, not by the source.

  1. Sow outdoors and leave it

    Up in April.

No stated waiting before sowing.

62% germination.

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

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Asclepias p. 23Public domain
Show the original text
Asclepias (Asclepiadaceae). A. cryptoceras germ. OT{5/8 in April), 70D(4/8 in 3rd w); and 40-70(6/7 in 1-3 d) using fresh seed. A second sample DS 3 m germ. OT(6/6 in April), 40-70(5/7 in 1-4 w), and 70-40-70-40-70(2/6 on 4th d), but after DS 6 m, it germ. 40-70(1/6 on 2nd d, rest rotted) and 70(all rotted) indicating that nearly all had died after 6 m DS.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Asclepias p. 23. 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, 1996

Difficulty Moderate 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. Then 21 days to germinate.

50% germination in 21 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Asclepias p. 23Public domain
Show the original text
Asclepias (Asclepiadaceae). A. cryptoceras germ. OT{5/8 in April), 70D(4/8 in 3rd w); and 40-70(6/7 in 1-3 d) using fresh seed. A second sample DS 3 m germ. OT(6/6 in April), 40-70(5/7 in 1-4 w), and 70-40-70-40-70(2/6 on 4th d), but after DS 6 m, it germ. 40-70(1/6 on 2nd d, rest rotted) and 70(all rotted) indicating that nearly all had died after 6 m DS.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Asclepias p. 23. 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 6

DerivedN. C. Deno, 1996

Difficulty High Rated by us, not by the source.

Start around January 7, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on January 6, 2026.

  1. Dry storage

    Duration: 90 daysTemperature: 70°F 21°C

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

  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 15 months from start to step 6. Germination happens during step 6, in 4 days.

33% germination in 4 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Asclepias p. 23Public domain
Show the original text
Asclepias (Asclepiadaceae). A. cryptoceras germ. OT{5/8 in April), 70D(4/8 in 3rd w); and 40-70(6/7 in 1-3 d) using fresh seed. A second sample DS 3 m germ. OT(6/6 in April), 40-70(5/7 in 1-4 w), and 70-40-70-40-70(2/6 on 4th d), but after DS 6 m, it germ. 40-70(1/6 on 2nd d, rest rotted) and 70(all rotted) indicating that nearly all had died after 6 m DS.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Asclepias p. 23. 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 7

DerivedN. C. Deno, 1996

Difficulty High Rated by us, not by the source.

Start around July 8, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on July 7, 2026.

  1. Dry storage

    Duration: 180 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

about 9 months from start to step 3. Germination happens during step 3, in 2 days.

17% germination in 2 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Asclepias p. 23Public domain
Show the original text
Asclepias (Asclepiadaceae). A. cryptoceras germ. OT{5/8 in April), 70D(4/8 in 3rd w); and 40-70(6/7 in 1-3 d) using fresh seed. A second sample DS 3 m germ. OT(6/6 in April), 40-70(5/7 in 1-4 w), and 70-40-70-40-70(2/6 on 4th d), but after DS 6 m, it germ. 40-70(1/6 on 2nd d, rest rotted) and 70(all rotted) indicating that nearly all had died after 6 m DS.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Asclepias p. 23. 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

Add to My Garden

View species page