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Polemonium viscosum

Skunk Jacob's-ladder · Skunk Polemonium · Sticky Jacob's-ladder · Sticky Polemonium

Family PolemoniaceaeGenus Polemonium

Pale blue flowers with orange anthers, clustered above a dense mound of sticky ferny leaves growing from a crack in gray rock.
FlowerJ BrewCC BY-SA 2.0

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
PurpleWikipedia
Native range
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; Wikipedia — Wikipedia contributors.

Worth knowing

  • Sky pilot, also called skunkweed and sticky Jacob's ladder, grows at high altitudes on dry, rocky sites in western North America. Wikipedia: Polemonium viscosum

This source reports 4 treatments. All are shown.

Protocol 1

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 and cover

    Temperature: 70°F 21°C

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

42% germination in 4–10 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Polemonium p. 195Public domain
Show the original text
Polemonium (Polemoniaceae). The following germ: in 2-5 w at 70: P. viscosum germ. 70(42% in 4-10 d) and 40(19% in 3-8 w)-70. It is unusual for such a high alpine species to show immediate germination at 70.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Polemonium p. 195. 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: light

No stated waiting before sowing. Then 21 days to germinate.

25% germination in 21 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Polemonium p. 195Public domain
Show the original text
Polemonium (Polemoniaceae). The following germ: in 2-5 w at 70: P. grayanum germ. 70L(25% in 3rd w), 70D(5%), and none in 700-40-70L indicating that light promotes germination.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Polemonium p. 195. 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 High Rated by us, not by the source.

Start around February 8, 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

Steps after step 1 run on after germination.

Germination happens during step 1, in 56 days.

19% germination in 21–56 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Polemonium p. 195Public domain
Show the original text
Polemonium (Polemoniaceae). The following germ: in 2-5 w at 70: P. viscosum germ. 70(42% in 4-10 d) and 40(19% in 3-8 w)-70. It is unusual for such a high alpine species to show immediate germination at 70.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Polemonium p. 195. 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 Very 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.

5% germination.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Polemonium p. 195Public domain
Show the original text
Polemonium (Polemoniaceae). The following germ: in 2-5 w at 70: P. grayanum germ. 70L(25% in 3rd w), 70D(5%), and none in 700-40-70L indicating that light promotes germination.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Polemonium p. 195. 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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