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Penstemon hirsutus

Hairy Beardtongue · Northeastern Beardtongue

Family PlantaginaceaeGenus Penstemon

Lilac tubes with white flared mouths, hanging on fine stalks from wiry stems above broken limestone.
FlowerD. Gordon E. RobertsonCC BY-SA 3.0

About the plant

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

The plant

Habit
Herbaceous PerennialExtension Gardener Plant Toolbox
Habit
perennialPlants of the World Online
Flower
Purple/Lavender, WhiteExtension Gardener Plant Toolbox
Blooms
Spring, SummerExtension Gardener Plant Toolbox
Native range
Canada, lower 48 statesPLANTS Database
Hardiness zones
3-9Extension Gardener Plant Toolbox

Growing conditions

Sun
Dappled Sunlight; Full sun; Partial ShadeExtension Gardener Plant Toolbox
Soil
Loam (Silt), Shallow RockyExtension Gardener Plant Toolbox
Moisture
Good Drainage, Occasionally DryExtension Gardener Plant Toolbox

Toxicity is noted only where a source states it. No note here is not a finding of safety.

Sources: Extension Gardener Plant Toolbox — NC State Extension; Plants of the World Online — Royal Botanic Gardens, Kew; PLANTS Database — USDA NRCS.

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 28, 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: light

about 3 months from start to step 2. Germination happens during step 2, in 8 days.

71% germination in 4–8 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Penstemon p. 187Public domain
Show the original text
Penstemon (Scrophulariaceae). Four types of germination were observed. Most Rocky Mountain species of a perennial nature germ. largely at 40 and often sowing at 70 was fatal or near fatal. A second group are short lived species that can flower the first year from seed typified by P. hirsutus requires light for germination, and germination is promoted by a preliminary 3 m at 40. Seeds germ. 40-70L(71% in 4-8 d), 70L(6% in 1-6 w), 70D(none), and 40-70D(none) using fresh seed or seed DS 6 m at 70. P. hirsutus pygmaea requires light. Fresh seed or seed IDS m at 70 germ. 70L(65% in 1-11 w), 40-70L(56% in 4-8 d), and none in 70D or 40-70D(none).
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Penstemon p. 187. 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 Moderate Rated by us, not by the source.

Start around January 18, 2027 for a May 3 last frost.

  1. Sow and cover

    Temperature: 70°F 21°C Light: light

No stated waiting before sowing. Then 77 days to germinate.

65% germination in 7–77 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Penstemon p. 187Public domain
Show the original text
Penstemon (Scrophulariaceae). Four types of germination were observed. Most Rocky Mountain species of a perennial nature germ. largely at 40 and often sowing at 70 was fatal or near fatal. A second group are short lived species that can flower the first year from seed typified by P. hirsutus requires light for germination, and germination is promoted by a preliminary 3 m at 40. Seeds germ. 40-70L(71% in 4-8 d), 70L(6% in 1-6 w), 70D(none), and 40-70D(none) using fresh seed or seed DS 6 m at 70. P. hirsutus pygmaea requires light. Fresh seed or seed IDS m at 70 germ. 70L(65% in 1-11 w), 40-70L(56% in 4-8 d), and none in 70D or 40-70D(none).
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Penstemon p. 187. 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 28, 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: light

about 3 months from start to step 2. Germination happens during step 2, in 8 days.

56% germination in 4–8 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Penstemon p. 187Public domain
Show the original text
Penstemon (Scrophulariaceae). Four types of germination were observed. Most Rocky Mountain species of a perennial nature germ. largely at 40 and often sowing at 70 was fatal or near fatal. A second group are short lived species that can flower the first year from seed typified by P. hirsutus requires light for germination, and germination is promoted by a preliminary 3 m at 40. Seeds germ. 40-70L(71% in 4-8 d), 70L(6% in 1-6 w), 70D(none), and 40-70D(none) using fresh seed or seed DS 6 m at 70. P. hirsutus pygmaea requires light. Fresh seed or seed IDS m at 70 germ. 70L(65% in 1-11 w), 40-70L(56% in 4-8 d), and none in 70D or 40-70D(none).
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Penstemon p. 187. 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 February 22, 2027 for a May 3 last frost.

  1. Sow and cover

    Temperature: 70°F 21°C Light: light

No stated waiting before sowing. Then 42 days to germinate.

6% germination in 7–42 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Penstemon p. 187Public domain
Show the original text
Penstemon (Scrophulariaceae). Four types of germination were observed. Most Rocky Mountain species of a perennial nature germ. largely at 40 and often sowing at 70 was fatal or near fatal. A second group are short lived species that can flower the first year from seed typified by P. hirsutus requires light for germination, and germination is promoted by a preliminary 3 m at 40. Seeds germ. 40-70L(71% in 4-8 d), 70L(6% in 1-6 w), 70D(none), and 40-70D(none) using fresh seed or seed DS 6 m at 70. P. hirsutus pygmaea requires light. Fresh seed or seed IDS m at 70 germ. 70L(65% in 1-11 w), 40-70L(56% in 4-8 d), and none in 70D or 40-70D(none).
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Penstemon p. 187. 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

  1. Sow and cover

    Temperature: 70°F 21°C Light: dark

No stated waiting before sowing.

0% germination.

Nothing germinated at 70.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Penstemon p. 187Public domain
Show the original text
Penstemon (Scrophulariaceae). Four types of germination were observed. Most Rocky Mountain species of a perennial nature germ. largely at 40 and often sowing at 70 was fatal or near fatal. A second group are short lived species that can flower the first year from seed typified by P. hirsutus requires light for germination, and germination is promoted by a preliminary 3 m at 40. Seeds germ. 40-70L(71% in 4-8 d), 70L(6% in 1-6 w), 70D(none), and 40-70D(none) using fresh seed or seed DS 6 m at 70. P. hirsutus pygmaea requires light. Fresh seed or seed IDS m at 70 germ. 70L(65% in 1-11 w), 40-70L(56% in 4-8 d), and none in 70D or 40-70D(none).
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Penstemon p. 187. Quoted exactly. Every value on this card comes from this record; 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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