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Bupleurum rotundifolium

Hare's Ear · Thorow-wax · Round-leaved Thoroughwax

Family ApiaceaeGenus Bupleurum

Tiny yellow flower clusters cupped in rosettes of pointed yellow-green bracts, with a round leaf pierced by the stem
FlowerStefan.lefnaerCC BY-SA 3.0

About the plant

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

The plant

Habit
AnnualExtension Gardener Plant Toolbox
Habit
annualPlants of the World Online
Height
1.3-2 ft40-60 cmExtension Gardener Plant Toolbox
Spread
1-1.3 ft30-40 cmExtension Gardener Plant Toolbox
Flower
Gold/Yellow, GreenExtension Gardener Plant Toolbox
Blooms
Fall, SummerExtension Gardener Plant Toolbox
Native range
Albania, Algeria, Austria, Belarus, Belgium, Bulgaria and elsewhereGBIF Backbone Taxonomy
Hardiness zones
5-9Extension Gardener Plant Toolbox

Growing conditions

Sun
Full sunExtension Gardener Plant Toolbox
Soil
Loam (Silt), SandExtension Gardener Plant Toolbox
Soil pH
Acid (<6.0), Alkaline (>8.0), Neutral (6.0-8.0)Extension Gardener Plant Toolbox
Moisture
Good Drainage, Moist, 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; GBIF Backbone Taxonomy — Global Biodiversity Information Facility.

Worth knowing

  • Hare's ear, native from North Africa and Europe to Central Asia, does well on disturbed ground and is now an established weed in the eastern United States and in South Africa. Wikipedia: Bupleurum rotundifolium

Two sources report 13 treatments between them. All are shown.

Protocol 1

DerivedN. C. Deno, 1998

Difficulty Low Rated by us, not by the source.

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

  1. Cold moist stratification

    Temperature: 40°F 4°C

Germination happens during step 1, in 28 days.

92% germination in 28 days.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Bupleurum p. 20Public domain
Show the original text
Bupleurum (Apiaceae). The three species were received in Feb. and presumably had been DS about 6 m. An additional 1 y of DS at 70 was fatal for B. rotundifolium germ. 40(92% in 4th w) and-70D(12% in 2nd w)-40(40% in 4th w). OT treatment was essentialiy equivalent to the germination at 40. A second sample germ. 40(90% in 4th w) and 70D(77% in 1-3 w).
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Bupleurum p. 20. 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 Low Rated by us, not by the source.

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

  1. Cold moist stratification

    Temperature: 40°F 4°C

Germination happens during step 1, in 28 days.

90% germination in 28 days.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Bupleurum p. 20Public domain
Show the original text
Bupleurum (Apiaceae). The three species were received in Feb. and presumably had been DS about 6 m. An additional 1 y of DS at 70 was fatal for B. rotundifolium germ. 40(92% in 4th w) and-70D(12% in 2nd w)-40(40% in 4th w). OT treatment was essentialiy equivalent to the germination at 40. A second sample germ. 40(90% in 4th w) and 70D(77% in 1-3 w).
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Bupleurum p. 20. 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 15, 2027 for a May 3 last frost.

  1. Sow and cover

    Temperature: 70°F 21°C Light: dark

No stated waiting before sowing. Then 21 days to germinate.

77% germination in 7–21 days.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Bupleurum p. 20Public domain
Show the original text
Bupleurum (Apiaceae). The three species were received in Feb. and presumably had been DS about 6 m. An additional 1 y of DS at 70 was fatal for B. rotundifolium germ. 40(92% in 4th w) and-70D(12% in 2nd w)-40(40% in 4th w). OT treatment was essentialiy equivalent to the germination at 40. A second sample germ. 40(90% in 4th w) and 70D(77% in 1-3 w).
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Bupleurum p. 20. 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 Moderate Rated by us, not by the source.

Start around December 8, 2026 for a May 3 last frost.

  1. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C Light: dark

    12 germinated in this phase.

  2. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

about 3 months from start to step 2. Germination happens during step 2, in 28 days.

40% germination in 28 days.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Bupleurum p. 20Public domain
Show the original text
Bupleurum (Apiaceae). The three species were received in Feb. and presumably had been DS about 6 m. An additional 1 y of DS at 70 was fatal for B. rotundifolium germ. 40(92% in 4th w) and-70D(12% in 2nd w)-40(40% in 4th w). OT treatment was essentialiy equivalent to the germination at 40. A second sample germ. 40(90% in 4th w) and 70D(77% in 1-3 w).
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Bupleurum p. 20. 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, 1996

Difficulty Low Rated by us, not by the source.

Start around September 10, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on September 9, 2026.

  1. Dry storage

    Duration: 180 daysTemperature: 70°F 21°C

  2. Cold moist stratification

    Temperature: 40°F 4°C

about 6 months from start to step 2. Germination happens during step 2, in 28 days.

92% germination in 28 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Bupleurum p. 26Public domain
Show the original text
Bupleurum (Apiaceae). B. rotundifolium germ. best at 40. Seeds DS 6 m germ. 40(90% in 4th w), 70D(77% in 1-3 w)-40(4% in 3rd w), 70L(48% in 1-7 w)-40(12%), and 70 GA-3(13%). Seed DS 1 y gave the same germination. A second sample also DS 6 m germ. 40(92% in 4th w), 70D(14% in 1-8 w)-40(27% in 4th w), 70L(11%)-40(52% in 4th w), and OT(87% in March, started in Feb.). The OT treatment was in effect germination at 40. About half the seeds died after 2 y DS as shown by 40(38% in 5-7 w).
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Bupleurum p. 26. 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, 1996

Difficulty Low Rated by us, not by the source.

Start around September 10, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on September 9, 2026.

  1. Dry storage

    Duration: 180 daysTemperature: 70°F 21°C

  2. Cold moist stratification

    Temperature: 40°F 4°C

about 6 months from start to step 2. Germination happens during step 2, in 28 days.

90% germination in 28 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Bupleurum p. 26Public domain
Show the original text
Bupleurum (Apiaceae). B. rotundifolium germ. best at 40. Seeds DS 6 m germ. 40(90% in 4th w), 70D(77% in 1-3 w)-40(4% in 3rd w), 70L(48% in 1-7 w)-40(12%), and 70 GA-3(13%). Seed DS 1 y gave the same germination. A second sample also DS 6 m germ. 40(92% in 4th w), 70D(14% in 1-8 w)-40(27% in 4th w), 70L(11%)-40(52% in 4th w), and OT(87% in March, started in Feb.). The OT treatment was in effect germination at 40. About half the seeds died after 2 y DS as shown by 40(38% in 5-7 w).
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Bupleurum p. 26. 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, 1996

Difficulty Low Rated by us, not by the source.

Sow around February 2027 — a date the source gives, not one counted back from a May 3 last frost.

  1. Dry storage

    Duration: 180 daysTemperature: 70°F 21°C

  2. Sow outdoors and leave it

    Sown outdoors in February; up in March.

about 6 months from start to sowing. Then 30 days to germinate.

87% germination in 30 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Bupleurum p. 26Public domain
Show the original text
Bupleurum (Apiaceae). B. rotundifolium germ. best at 40. Seeds DS 6 m germ. 40(90% in 4th w), 70D(77% in 1-3 w)-40(4% in 3rd w), 70L(48% in 1-7 w)-40(12%), and 70 GA-3(13%). Seed DS 1 y gave the same germination. A second sample also DS 6 m germ. 40(92% in 4th w), 70D(14% in 1-8 w)-40(27% in 4th w), 70L(11%)-40(52% in 4th w), and OT(87% in March, started in Feb.). The OT treatment was in effect germination at 40. About half the seeds died after 2 y DS as shown by 40(38% in 5-7 w).
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Bupleurum p. 26. 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, 1996

Difficulty Moderate Rated by us, not by the source.

Start around September 17, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on September 16, 2026.

  1. Dry storage

    Duration: 180 daysTemperature: 70°F 21°C

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C Light: dark

  3. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

    4 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 21 days.

77% germination in 7–21 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Bupleurum p. 26Public domain
Show the original text
Bupleurum (Apiaceae). B. rotundifolium germ. best at 40. Seeds DS 6 m germ. 40(90% in 4th w), 70D(77% in 1-3 w)-40(4% in 3rd w), 70L(48% in 1-7 w)-40(12%), and 70 GA-3(13%). Seed DS 1 y gave the same germination. A second sample also DS 6 m germ. 40(92% in 4th w), 70D(14% in 1-8 w)-40(27% in 4th w), 70L(11%)-40(52% in 4th w), and OT(87% in March, started in Feb.). The OT treatment was in effect germination at 40. About half the seeds died after 2 y DS as shown by 40(38% in 5-7 w).
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Bupleurum p. 26. 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, 1996

Difficulty Moderate Rated by us, not by the source.

Start around June 12, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on June 11, 2026.

  1. Dry storage

    Duration: 180 daysTemperature: 70°F 21°C

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C Light: light

    11 germinated in this phase.

  3. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

about 9 months from start to step 3. Germination happens during step 3, in 28 days.

52% germination in 28 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Bupleurum p. 26Public domain
Show the original text
Bupleurum (Apiaceae). B. rotundifolium germ. best at 40. Seeds DS 6 m germ. 40(90% in 4th w), 70D(77% in 1-3 w)-40(4% in 3rd w), 70L(48% in 1-7 w)-40(12%), and 70 GA-3(13%). Seed DS 1 y gave the same germination. A second sample also DS 6 m germ. 40(92% in 4th w), 70D(14% in 1-8 w)-40(27% in 4th w), 70L(11%)-40(52% in 4th w), and OT(87% in March, started in Feb.). The OT treatment was in effect germination at 40. About half the seeds died after 2 y DS as shown by 40(38% in 5-7 w).
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Bupleurum p. 26. 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 Moderate Rated by us, not by the source.

Start around August 20, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on August 19, 2026.

  1. Dry storage

    Duration: 180 daysTemperature: 70°F 21°C

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C Light: light

  3. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

    12 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 49 days.

48% germination in 7–49 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Bupleurum p. 26Public domain
Show the original text
Bupleurum (Apiaceae). B. rotundifolium germ. best at 40. Seeds DS 6 m germ. 40(90% in 4th w), 70D(77% in 1-3 w)-40(4% in 3rd w), 70L(48% in 1-7 w)-40(12%), and 70 GA-3(13%). Seed DS 1 y gave the same germination. A second sample also DS 6 m germ. 40(92% in 4th w), 70D(14% in 1-8 w)-40(27% in 4th w), 70L(11%)-40(52% in 4th w), and OT(87% in March, started in Feb.). The OT treatment was in effect germination at 40. About half the seeds died after 2 y DS as shown by 40(38% in 5-7 w).
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Bupleurum p. 26. 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 Moderate Rated by us, not by the source.

Start around February 16, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on February 15, 2025.

  1. Dry storage

    Duration: 730 daysTemperature: 70°F 21°C

  2. Cold moist stratification

    Temperature: 40°F 4°C

about 2 years from start to step 2. Germination happens during step 2, in 49 days.

38% germination in 35–49 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Bupleurum p. 26Public domain
Show the original text
Bupleurum (Apiaceae). B. rotundifolium germ. best at 40. Seeds DS 6 m germ. 40(90% in 4th w), 70D(77% in 1-3 w)-40(4% in 3rd w), 70L(48% in 1-7 w)-40(12%), and 70 GA-3(13%). Seed DS 1 y gave the same germination. A second sample also DS 6 m germ. 40(92% in 4th w), 70D(14% in 1-8 w)-40(27% in 4th w), 70L(11%)-40(52% in 4th w), and OT(87% in March, started in Feb.). The OT treatment was in effect germination at 40. About half the seeds died after 2 y DS as shown by 40(38% in 5-7 w).
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Bupleurum p. 26. 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 June 12, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on June 11, 2026.

  1. Dry storage

    Duration: 180 daysTemperature: 70°F 21°C

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C Light: dark

    14 germinated in this phase.

  3. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

about 9 months from start to step 3. Germination happens during step 3, in 28 days.

27% germination in 28 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Bupleurum p. 26Public domain
Show the original text
Bupleurum (Apiaceae). B. rotundifolium germ. best at 40. Seeds DS 6 m germ. 40(90% in 4th w), 70D(77% in 1-3 w)-40(4% in 3rd w), 70L(48% in 1-7 w)-40(12%), and 70 GA-3(13%). Seed DS 1 y gave the same germination. A second sample also DS 6 m germ. 40(92% in 4th w), 70D(14% in 1-8 w)-40(27% in 4th w), 70L(11%)-40(52% in 4th w), and OT(87% in March, started in Feb.). The OT treatment was in effect germination at 40. About half the seeds died after 2 y DS as shown by 40(38% in 5-7 w).
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Bupleurum p. 26. 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 13

DerivedN. C. Deno, 1996

Difficulty High Rated by us, not by the source.

Start around September 17, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on September 16, 2026.

  1. Dry storage

    Duration: 180 daysTemperature: 70°F 21°C

  2. Gibberellic acid soak

  3. Sow and cover

    Temperature: 70°F 21°C

about 6 months from start to sowing. Germination time not stated; 21 days assumed.

13% germination.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Bupleurum p. 26Public domain
Show the original text
Bupleurum (Apiaceae). B. rotundifolium germ. best at 40. Seeds DS 6 m germ. 40(90% in 4th w), 70D(77% in 1-3 w)-40(4% in 3rd w), 70L(48% in 1-7 w)-40(12%), and 70 GA-3(13%). Seed DS 1 y gave the same germination. A second sample also DS 6 m germ. 40(92% in 4th w), 70D(14% in 1-8 w)-40(27% in 4th w), 70L(11%)-40(52% in 4th w), and OT(87% in March, started in Feb.). The OT treatment was in effect germination at 40. About half the seeds died after 2 y DS as shown by 40(38% in 5-7 w).
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Bupleurum p. 26. 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

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