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Sabatia kennedyana

Plymouth Gentian · Plymouth Rose Gentian · Large Sabatia

Family GentianaceaeGenus Sabatia

Pink flowers with yellow centers and overlapping petals
FlowerSesamehoneytartCC BY-SA 4.0

About the plant

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

The plant

Habit
Herbaceous perennialPlant Finder
Habit
monocarpic perennialPlants of the World Online
Height
2.5-3 ft75-90 cmPlant Finder
Spread
2.5-3 ft75-90 cmPlant Finder
Flower
Showy; pink and white with a yellow and red eyePlant Finder
Blooms
June to AugustPlant Finder
Native range
Eastern North AmericaPlant Finder
Hardiness zones
6-9Plant Finder
Note
Sowing at 40 is fatal -- nothing over three cycles. A cold period after germination is fine.Seed Germination Theory and Practice, 2nd ed.

Growing conditions

Sun
Full sunPlant Finder
Soil
Wet, boggyPlant Finder
Moisture
WetPlant Finder
Watering
WetPlant Finder

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

Sources: Plant Finder — Missouri Botanical Garden; Plants of the World Online — Royal Botanic Gardens, Kew; Seed Germination Theory and Practice, 2nd ed. — N. C. Deno.

Worth knowing

  • Plymouth rose gentian has a scattered range, from Nova Scotia and Massachusetts to the Carolinas. It is threatened by shoreline development, off-road vehicles, hydroelectric dams, pollution and poaching. Wikipedia: Sabatia kennedyana

This source reports two treatments. Both are shown.

Protocol 1

DerivedN. C. Deno, 1993

Difficulty Moderate Rated by us, not by the source.

Start around March 1, 2027 for a May 3 last frost.

  1. Warm moist stratification

    Temperature: 70°F 21°C

    42%, over 2-5 weeks.

  2. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

    Deno gives no length for this period; three months is his standard cycle.

  3. Warm moist stratification

    Temperature: 70°F 21°C

    A further 30%, in 6-8 days.

Steps after step 1 run on after germination.

Germination happens during step 1, in 35 days.

42% germination in 14–35 days.

42% at 70, then 30% more after the cycle. Sow warm: sowing at 40 kills it.

This source doesn't state how long step 3 lasts.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, SabatiaPublic domain
Show the original text
Sabatia ( Gentianaceae). S. kennedyana germ. 70(42% in 2-5 w)-40-70(30% in 6-8 d) and none at 40 even after 3 cycles showing that sowing at 40 is fatal.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Sabatia. 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

  1. Cold moist stratification

    Temperature: 40°F 4°C

    Nothing, even after three cycles.

Germination happens during step 1.

0% germination.

Nothing over three cycles. Deno calls sowing at 40 fatal for this species.

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

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, SabatiaPublic domain
Show the original text
Sabatia ( Gentianaceae). S. kennedyana germ. 70(42% in 2-5 w)-40-70(30% in 6-8 d) and none at 40 even after 3 cycles showing that sowing at 40 is fatal.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Sabatia. 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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