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Penstemon virens

Front Range Beardtongue · Blue Mist Penstemon

Family PlantaginaceaeGenus Penstemon

A low mound of narrow leaves throwing up many thin stems of pale lilac-blue flowers, spreading over gray gravel.
The whole plantDave Powell, USDA FS, bugwood.orgPublic 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/herb, SubshrubPLANTS Database
Flower
BlueWikipedia
Native range
Colorado, WyomingGBIF Backbone Taxonomy

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; GBIF Backbone Taxonomy — Global Biodiversity Information Facility.

Worth knowing

  • Virens comes from the Latin vireō, "I am green", and as green beardtongue it is named for its particularly green, shiny leaves. The name blue mist penstemon may refer to its cloud of flowers on many stems, facing every direction. Wikipedia: Penstemon virens

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 July 16, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on July 15, 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

    5 germinated in this phase.

Steps after step 2 run on after germination.

about 6 months from start to step 2. Germination happens during step 2, in 84 days.

30% germination in 28–84 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. virens germ. best with seed DS 6 m at 70 in 40(30% in 4-12 w)-70(5% in 1-3 d). The DS is essential as seed DS 6 m at 40 germ. less as shown by 40(8% in 7-12 w)-70(1%) and fresh seed germ. none in 40-70 treatment. Germination failed with both DS seed and fresh seed when sown at 70. The above data were for seed collected in July. If the seed is allowed to remain on the dry stems all winter and collected in March, the effect is like DS and the seed germ. 40(11%)-70(17%).
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 High Rated by us, not by the source.

Start around June 19, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on June 18, 2026.

  1. Dry storage

    Duration: 180 days

  2. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

    11 germinated in this phase.

  3. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

about 9 months from start to step 3. Germination happens during step 3; time not stated, 21 days assumed.

17% germination.

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. virens germ. best with seed DS 6 m at 70 in 40(30% in 4-12 w)-70(5% in 1-3 d). The DS is essential as seed DS 6 m at 40 germ. less as shown by 40(8% in 7-12 w)-70(1%) and fresh seed germ. none in 40-70 treatment. Germination failed with both DS seed and fresh seed when sown at 70. The above data were for seed collected in July. If the seed is allowed to remain on the dry stems all winter and collected in March, the effect is like DS and the seed germ. 40(11%)-70(17%).
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 Very high Rated by us, not by the source.

Start around July 16, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on July 15, 2026.

  1. Dry storage

    Duration: 180 daysTemperature: 40°F 4°C

  2. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  3. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    1 germinated in this phase.

Steps after step 2 run on after germination.

about 6 months from start to step 2. Germination happens during step 2, in 84 days.

8% germination in 49–84 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. virens germ. best with seed DS 6 m at 70 in 40(30% in 4-12 w)-70(5% in 1-3 d). The DS is essential as seed DS 6 m at 40 germ. less as shown by 40(8% in 7-12 w)-70(1%) and fresh seed germ. none in 40-70 treatment. Germination failed with both DS seed and fresh seed when sown at 70. The above data were for seed collected in July. If the seed is allowed to remain on the dry stems all winter and collected in March, the effect is like DS and the seed germ. 40(11%)-70(17%).
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

  1. Cold moist stratification

    Temperature: 40°F 4°C

Germination happens during step 1.

0% germination.

Nothing germinated at 40.

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

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. virens germ. best with seed DS 6 m at 70 in 40(30% in 4-12 w)-70(5% in 1-3 d). The DS is essential as seed DS 6 m at 40 germ. less as shown by 40(8% in 7-12 w)-70(1%) and fresh seed germ. none in 40-70 treatment. Germination failed with both DS seed and fresh seed when sown at 70. The above data were for seed collected in July. If the seed is allowed to remain on the dry stems all winter and collected in March, the effect is like DS and the seed germ. 40(11%)-70(17%).
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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