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Platycodon grandiflorus

Balloon-flower · Chinese-bellflower · Platycodon

Family CampanulaceaeGenus Platycodon

A violet-blue bell flower opened into five pointed lobes with darker veins, beside two inflated cream buds like small balloons.
FlowerKrzysztof GolikCC BY-SA 4.0

About the plant

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

The plant

Habit
PerennialExtension Gardener Plant Toolbox
Habit
perennialPlants of the World Online
Height
1-2 ft30-60 cmExtension Gardener Plant Toolbox
Spread
1-1.5 ft30-45 cmExtension Gardener Plant Toolbox
Flower
Blue, WhiteExtension Gardener Plant Toolbox
Blooms
Spring, SummerExtension Gardener Plant Toolbox
Native range
Amur, China North-Central, China South-Central, China Southeast, Chita, Inner Mongolia and elsewhereGBIF Backbone Taxonomy
Hardiness zones
3-8Extension Gardener Plant Toolbox

Growing conditions

Sun
Full sun; Partial ShadeExtension Gardener Plant Toolbox
Soil
Loam (Silt)Extension Gardener Plant Toolbox
Soil pH
Acid (<6.0)Extension Gardener Plant Toolbox
Moisture
Good DrainageExtension 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

  • Platycodon is Greek for flat bell, and balloon flower is for its swollen buds. The only species in its genus. Wikipedia: Platycodon
  • In Korea the root, doraji, is one of the most common namul vegetables and a frequent ingredient in bibimbap. Wikipedia: 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 January 1, 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

about 3 months from start to step 2. Germination happens during step 2, in 4 days.

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 days

  2. Cold moist stratification

    Temperature: 40°F 4°C

about 6 months from start to step 2. Germination happens during step 2, in 70 days.

88% germination in 21–70 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 3

DerivedN. C. Deno, 1993

Difficulty Low Rated by us, not by the source.

Start around October 1, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on September 30, 2026.

  1. Dry storage

    Duration: 180 days

  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.

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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