Deno’s Garden

Platycodon grandiflorus

Genus Platycodon

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 October 3, 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

about 6 months from start to sowing. Then 4 days to germinate.

100% germination in 2–4 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Platycodon p. 194Public domain
Show the original text
Platycodon (Campanulaceae). P. grandiflora germ. 70(68% in 5-6 d) and 40-70(100% in 2-4 d). Seed DS 6 m at 70 or 40 germ. 70(87% in 2-7 d) and 40(88% in 3-10 w). DS caused seeds to germinate at 40 as well as 70.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Platycodon p. 194. 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 Low Rated by us, not by the source.

Start around July 30, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on July 29, 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 sowing. Then 70 days to germinate.

88% germination in 21–70 days.

This source doesn't state how long.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Platycodon p. 194Public domain
Show the original text
Platycodon (Campanulaceae). P. grandiflora germ. 70(68% in 5-6 d) and 40-70(100% in 2-4 d). Seed DS 6 m at 70 or 40 germ. 70(87% in 2-7 d) and 40(88% in 3-10 w). DS caused seeds to germinate at 40 as well as 70.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Platycodon p. 194. 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 Low Rated by us, not by the source.

Start around September 30, 2026 for a May 3 last frost.

  1. Dry storage

    Duration: 180 daysTemperature: 70°F 21°C

  2. Sow and cover

    Temperature: 70°F 21°C

about 6 months from start to sowing. Then 7 days to germinate.

87% germination in 2–7 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Platycodon p. 194Public domain
Show the original text
Platycodon (Campanulaceae). P. grandiflora germ. 70(68% in 5-6 d) and 40-70(100% in 2-4 d). Seed DS 6 m at 70 or 40 germ. 70(87% in 2-7 d) and 40(88% in 3-10 w). DS caused seeds to germinate at 40 as well as 70.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Platycodon p. 194. 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

Difficulty Moderate Rated by us, not by the source.

Start around March 30, 2027 for a May 3 last frost.

  1. Sow and cover

    Temperature: 70°F 21°C

No stated waiting before sowing. Then 6 days to germinate.

68% germination in 5–6 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Platycodon p. 194Public domain
Show the original text
Platycodon (Campanulaceae). P. grandiflora germ. 70(68% in 5-6 d) and 40-70(100% in 2-4 d). Seed DS 6 m at 70 or 40 germ. 70(87% in 2-7 d) and 40(88% in 3-10 w). DS caused seeds to germinate at 40 as well as 70.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Platycodon p. 194. 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.