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Penstemon nitidus

Wax-leaf Beardtongue · Shining Penstemon · Smooth Blue Beardtongue · Waxleaf Penstemon

Family PlantaginaceaeGenus Penstemon

A low spreading plant with sky-blue flowers in dense clusters, their calyces flushed red-purple, over blue-gray clasping leaves.
The whole plantMatt Lavin from Bozeman, Montana, USACC 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/herb, SubshrubPLANTS Database
Flower
Light blue, medium blueWikipedia
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

This source reports two treatments. Both are shown.

Protocol 1

DerivedN. C. Deno, 1993

Difficulty Low Rated by us, not by the source.

Start around February 8, 2027 for a May 3 last frost.

  1. Cold moist stratification

    Temperature: 40°F 4°C

Germination happens during step 1, in 56 days.

95% germination in 21–56 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. nitidus germ. best with seed DS 6 m at 40 in 40(95% in 3-8 w) and less with fresh seed in 40(74% in 5-12 w)-70(3% in 2-3 d). Seeds sown at 70 and seeds DS for 6 m at 70 were dead.
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 11, 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

    3 germinated in this phase.

Steps after step 1 run on after germination.

Germination happens during step 1, in 84 days.

74% germination in 35–84 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. nitidus germ. best with seed DS 6 m at 40 in 40(95% in 3-8 w) and less with fresh seed in 40(74% in 5-12 w)-70(3% in 2-3 d). Seeds sown at 70 and seeds DS for 6 m at 70 were dead.
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.

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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