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Wahlenbergia congesta

Family CampanulaceaeGenus Wahlenbergia

A low mat of small rounded leaves among gray pebbles, scattered with white star-shaped flowers
FlowerJohn BarklaCC BY 4.0

About the plant

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

Habit
perennialPlants of the World Online
Flower
WhiteRead from the photograph on this page
Native range
New Zealand SouthGBIF 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; Read from the photograph on this page — Deno's Garden; GBIF Backbone Taxonomy — Global Biodiversity Information Facility.

Two sources report 12 treatments between them. All are shown.

Protocol 1

DerivedN. C. Deno, 1998

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.

100% germination in 8 days.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Wahlenbergia p. 67Public domain
Show the original text
Wahlenbergia (Campanulaceae). Generally light was required for . germination. It would help if this could be studied as a function of time of DS. W. congesta DS 6 m required light for germination. One sample germ. 70L(40% in 3rd w), 70D(none), 40-70L(100% on 8th d), and 40-70D(none). An earlier sample was similar (ist Suppl.). After DS 1 y seeds germ. 70L(97% in 1-3 w) and 70D(20% in 2nd w). There is no indication as yet of dying but the light requirement is slowly disappearing. After 2 y of DS seeds germ. 70D(35% in 2nd w) confirming the gradual disappearance of the light requirement. A sample labelled W. congesta hybrid also showed a light requirement though less dramatic. This germ. 70L(80% in 3rd w), 70D(19% in 2nd w), 40-70L(100% in 5-8 d), and 40-70D(4%).
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Wahlenbergia p. 67. 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, 1998

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.

100% germination in 5–8 days.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Wahlenbergia p. 67Public domain
Show the original text
Wahlenbergia (Campanulaceae). Generally light was required for . germination. It would help if this could be studied as a function of time of DS. W. congesta DS 6 m required light for germination. One sample germ. 70L(40% in 3rd w), 70D(none), 40-70L(100% on 8th d), and 40-70D(none). An earlier sample was similar (ist Suppl.). After DS 1 y seeds germ. 70L(97% in 1-3 w) and 70D(20% in 2nd w). There is no indication as yet of dying but the light requirement is slowly disappearing. After 2 y of DS seeds germ. 70D(35% in 2nd w) confirming the gradual disappearance of the light requirement. A sample labelled W. congesta hybrid also showed a light requirement though less dramatic. This germ. 70L(80% in 3rd w), 70D(19% in 2nd w), 40-70L(100% in 5-8 d), and 40-70D(4%).
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Wahlenbergia p. 67. 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, 1998

Difficulty Low Rated by us, not by the source.

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

  1. Dry storage

    Duration: 365 daysTemperature: 70°F 21°C

  2. Sow and cover

    Temperature: 70°F 21°C Light: light

about 12 months from start to sowing. Then 21 days to germinate.

97% germination in 7–21 days.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Wahlenbergia p. 67Public domain
Show the original text
Wahlenbergia (Campanulaceae). Generally light was required for . germination. It would help if this could be studied as a function of time of DS. W. congesta DS 6 m required light for germination. One sample germ. 70L(40% in 3rd w), 70D(none), 40-70L(100% on 8th d), and 40-70D(none). An earlier sample was similar (ist Suppl.). After DS 1 y seeds germ. 70L(97% in 1-3 w) and 70D(20% in 2nd w). There is no indication as yet of dying but the light requirement is slowly disappearing. After 2 y of DS seeds germ. 70D(35% in 2nd w) confirming the gradual disappearance of the light requirement. A sample labelled W. congesta hybrid also showed a light requirement though less dramatic. This germ. 70L(80% in 3rd w), 70D(19% in 2nd w), 40-70L(100% in 5-8 d), and 40-70D(4%).
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Wahlenbergia p. 67. 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, 1998

Difficulty Low 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.

80% germination in 21 days.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Wahlenbergia p. 67Public domain
Show the original text
Wahlenbergia (Campanulaceae). Generally light was required for . germination. It would help if this could be studied as a function of time of DS. W. congesta DS 6 m required light for germination. One sample germ. 70L(40% in 3rd w), 70D(none), 40-70L(100% on 8th d), and 40-70D(none). An earlier sample was similar (ist Suppl.). After DS 1 y seeds germ. 70L(97% in 1-3 w) and 70D(20% in 2nd w). There is no indication as yet of dying but the light requirement is slowly disappearing. After 2 y of DS seeds germ. 70D(35% in 2nd w) confirming the gradual disappearance of the light requirement. A sample labelled W. congesta hybrid also showed a light requirement though less dramatic. This germ. 70L(80% in 3rd w), 70D(19% in 2nd w), 40-70L(100% in 5-8 d), and 40-70D(4%).
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Wahlenbergia p. 67. 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, 1998

Difficulty Moderate 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.

40% germination in 21 days.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Wahlenbergia p. 67Public domain
Show the original text
Wahlenbergia (Campanulaceae). Generally light was required for . germination. It would help if this could be studied as a function of time of DS. W. congesta DS 6 m required light for germination. One sample germ. 70L(40% in 3rd w), 70D(none), 40-70L(100% on 8th d), and 40-70D(none). An earlier sample was similar (ist Suppl.). After DS 1 y seeds germ. 70L(97% in 1-3 w) and 70D(20% in 2nd w). There is no indication as yet of dying but the light requirement is slowly disappearing. After 2 y of DS seeds germ. 70D(35% in 2nd w) confirming the gradual disappearance of the light requirement. A sample labelled W. congesta hybrid also showed a light requirement though less dramatic. This germ. 70L(80% in 3rd w), 70D(19% in 2nd w), 40-70L(100% in 5-8 d), and 40-70D(4%).
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Wahlenbergia p. 67. 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 6

DerivedN. C. Deno, 1998

Difficulty Moderate Rated by us, not by the source.

Start around March 23, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on March 22, 2025.

  1. Dry storage

    Duration: 730 daysTemperature: 70°F 21°C

  2. Sow and cover

    Temperature: 70°F 21°C Light: dark

about 2 years from start to sowing. Then 14 days to germinate.

35% germination in 14 days.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Wahlenbergia p. 67Public domain
Show the original text
Wahlenbergia (Campanulaceae). Generally light was required for . germination. It would help if this could be studied as a function of time of DS. W. congesta DS 6 m required light for germination. One sample germ. 70L(40% in 3rd w), 70D(none), 40-70L(100% on 8th d), and 40-70D(none). An earlier sample was similar (ist Suppl.). After DS 1 y seeds germ. 70L(97% in 1-3 w) and 70D(20% in 2nd w). There is no indication as yet of dying but the light requirement is slowly disappearing. After 2 y of DS seeds germ. 70D(35% in 2nd w) confirming the gradual disappearance of the light requirement. A sample labelled W. congesta hybrid also showed a light requirement though less dramatic. This germ. 70L(80% in 3rd w), 70D(19% in 2nd w), 40-70L(100% in 5-8 d), and 40-70D(4%).
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Wahlenbergia p. 67. 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 7

DerivedN. C. Deno, 1998

Difficulty High Rated by us, not by the source.

Start around March 23, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on March 22, 2026.

  1. Dry storage

    Duration: 365 daysTemperature: 70°F 21°C

  2. Sow and cover

    Temperature: 70°F 21°C Light: dark

about 12 months from start to sowing. Then 14 days to germinate.

20% germination in 14 days.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Wahlenbergia p. 67Public domain
Show the original text
Wahlenbergia (Campanulaceae). Generally light was required for . germination. It would help if this could be studied as a function of time of DS. W. congesta DS 6 m required light for germination. One sample germ. 70L(40% in 3rd w), 70D(none), 40-70L(100% on 8th d), and 40-70D(none). An earlier sample was similar (ist Suppl.). After DS 1 y seeds germ. 70L(97% in 1-3 w) and 70D(20% in 2nd w). There is no indication as yet of dying but the light requirement is slowly disappearing. After 2 y of DS seeds germ. 70D(35% in 2nd w) confirming the gradual disappearance of the light requirement. A sample labelled W. congesta hybrid also showed a light requirement though less dramatic. This germ. 70L(80% in 3rd w), 70D(19% in 2nd w), 40-70L(100% in 5-8 d), and 40-70D(4%).
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Wahlenbergia p. 67. 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 8

DerivedN. C. Deno, 1998

Difficulty High Rated by us, not by the source.

Start around March 22, 2027 for a May 3 last frost.

  1. Sow and cover

    Temperature: 70°F 21°C Light: dark

No stated waiting before sowing. Then 14 days to germinate.

19% germination in 14 days.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Wahlenbergia p. 67Public domain
Show the original text
Wahlenbergia (Campanulaceae). Generally light was required for . germination. It would help if this could be studied as a function of time of DS. W. congesta DS 6 m required light for germination. One sample germ. 70L(40% in 3rd w), 70D(none), 40-70L(100% on 8th d), and 40-70D(none). An earlier sample was similar (ist Suppl.). After DS 1 y seeds germ. 70L(97% in 1-3 w) and 70D(20% in 2nd w). There is no indication as yet of dying but the light requirement is slowly disappearing. After 2 y of DS seeds germ. 70D(35% in 2nd w) confirming the gradual disappearance of the light requirement. A sample labelled W. congesta hybrid also showed a light requirement though less dramatic. This germ. 70L(80% in 3rd w), 70D(19% in 2nd w), 40-70L(100% in 5-8 d), and 40-70D(4%).
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Wahlenbergia p. 67. 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 9

DerivedN. C. Deno, 1998

Difficulty Very high Rated by us, not by the source.

Start around December 15, 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: dark

about 3 months from start to step 2. Germination happens during step 2; time not stated, 21 days assumed.

4% germination.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Wahlenbergia p. 67Public domain
Show the original text
Wahlenbergia (Campanulaceae). Generally light was required for . germination. It would help if this could be studied as a function of time of DS. W. congesta DS 6 m required light for germination. One sample germ. 70L(40% in 3rd w), 70D(none), 40-70L(100% on 8th d), and 40-70D(none). An earlier sample was similar (ist Suppl.). After DS 1 y seeds germ. 70L(97% in 1-3 w) and 70D(20% in 2nd w). There is no indication as yet of dying but the light requirement is slowly disappearing. After 2 y of DS seeds germ. 70D(35% in 2nd w) confirming the gradual disappearance of the light requirement. A sample labelled W. congesta hybrid also showed a light requirement though less dramatic. This germ. 70L(80% in 3rd w), 70D(19% in 2nd w), 40-70L(100% in 5-8 d), and 40-70D(4%).
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Wahlenbergia p. 67. 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 10

DerivedN. C. Deno, 1996

Difficulty Low Rated by us, not by the source.

Start around March 24, 2027 for a May 3 last frost.

  1. Gibberellic acid soak

  2. Sow and cover

    Temperature: 70°F 21°C

No stated waiting before sowing. Then 12 days to germinate.

100% germination in 8–12 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Wahlenbergia p. 86Public domain
Show the original text
Wahlenbergia (Campanulaceae). W. congesta germ. 70L(93% in 8-10 d), 70 GA-3(100% in 8-12 d), and 70D(10%).
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Wahlenbergia p. 86. 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 11

DerivedN. C. Deno, 1996

Difficulty Low 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 Light: light

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

93% germination in 8–10 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Wahlenbergia p. 86Public domain
Show the original text
Wahlenbergia (Campanulaceae). W. congesta germ. 70L(93% in 8-10 d), 70 GA-3(100% in 8-12 d), and 70D(10%).
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Wahlenbergia p. 86. 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 12

DerivedN. C. Deno, 1996

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: dark

No stated waiting before sowing. Germination time not stated; 21 days assumed.

10% germination.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Wahlenbergia p. 86Public domain
Show the original text
Wahlenbergia (Campanulaceae). W. congesta germ. 70L(93% in 8-10 d), 70 GA-3(100% in 8-12 d), and 70D(10%).
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Wahlenbergia p. 86. 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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