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Rhodotypos scandens

Black Jetbead · Jetbead

Family RosaceaeGenus Rhodotypos

White flowers of four broad overlapping petals around a small green center, among sharply toothed ribbed leaves.
FlowerAttribution information, such as the author's name, e-mail, website, or signature, that was once visible in the image itself has been moved into the image metadata and/or image description page. This makes the image easier to reuse and more language-neutral, and makes the text easier to process and search for. Commons discourages placing visible author information in images.CC BY-SA 3.0

About the plant

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

The plant

Habit
shrubPlants of the World Online
Habit
Perennial, ShrubPLANTS Database
Height
3-6 ft0.9-1.8 mExtension Gardener Plant Toolbox
Spread
4-9 ft1.2-2.7 mExtension Gardener Plant Toolbox
Flower
WhiteExtension Gardener Plant Toolbox
Blooms
Spring, SummerExtension Gardener Plant Toolbox
Native range
China North-Central, China Southeast, Japan, Korea, ManchuriaGBIF Backbone Taxonomy
Hardiness zones
4-8Extension Gardener Plant Toolbox

Growing conditions

Sun
Full sun; Partial ShadeExtension Gardener Plant Toolbox
Soil
Clay, High Organic Matter, Loam (Silt), Sand, Shallow RockyExtension Gardener Plant Toolbox
Soil pH
Acid (<6.0), Alkaline (>8.0), Neutral (6.0-8.0)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: Plants of the World Online — Royal Botanic Gardens, Kew; PLANTS Database — USDA NRCS; Extension Gardener Plant Toolbox — NC State Extension; GBIF Backbone Taxonomy — Global Biodiversity Information Facility.

Worth knowing

  • Rhodotypos scandens is the only species in its genus, closely related to Kerria. Its fruits are considered highly toxic to people and may be fatal if eaten. Wikipedia: Rhodotypos

This source reports 6 treatments. All are shown.

Protocol 1

DerivedN. C. Deno, 1993

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. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  3. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    16 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; time not stated, 21 days assumed.

65% germination.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Rhodotypos p. 205Public domain
Show the original text
Rhodotypos (Rosaceae). A. tetrapetala gave multicycle germination with germination occurring at both 70 and 40.' Seeds collected in January germ. 70- 40(44%)-70(16%)-40(12%) and 40(14%)-70(24%)-40-70(14%)-40(11%)-70(3%). Seed DS 6 m at 40 germ. 70-40-70(47%)-40(25%) and 40(57%)-70(17%)-40-70(2%)- 40. Seed DS 6 m at 70 germ. 70-40-70(43%)-40(28%) and 40(65%)-70(16%).
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Rhodotypos p. 205. 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 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. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  3. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    17 germinated in this phase.

  4. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  5. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    2 germinated in this phase.

  6. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

Steps after step 2 run on after germination.

about 6 months from start to step 2. Germination happens during step 2; time not stated, 21 days assumed.

57% germination.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Rhodotypos p. 205Public domain
Show the original text
Rhodotypos (Rosaceae). A. tetrapetala gave multicycle germination with germination occurring at both 70 and 40.' Seeds collected in January germ. 70- 40(44%)-70(16%)-40(12%) and 40(14%)-70(24%)-40-70(14%)-40(11%)-70(3%). Seed DS 6 m at 40 germ. 70-40-70(47%)-40(25%) and 40(57%)-70(17%)-40-70(2%)- 40. Seed DS 6 m at 70 germ. 70-40-70(43%)-40(28%) and 40(65%)-70(16%).
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Rhodotypos p. 205. 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 High Rated by us, not by the source.

Start around March 21, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on March 20, 2026.

  1. Dry storage

    Duration: 180 daysTemperature: 70°F 21°C

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

  3. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  4. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

  5. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

    25 germinated in this phase.

Steps after step 4 run on after germination.

about 12 months from start to step 4. Germination happens during step 4; time not stated, 21 days assumed.

47% germination.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Rhodotypos p. 205Public domain
Show the original text
Rhodotypos (Rosaceae). A. tetrapetala gave multicycle germination with germination occurring at both 70 and 40.' Seeds collected in January germ. 70- 40(44%)-70(16%)-40(12%) and 40(14%)-70(24%)-40-70(14%)-40(11%)-70(3%). Seed DS 6 m at 40 germ. 70-40-70(47%)-40(25%) and 40(57%)-70(17%)-40-70(2%)- 40. Seed DS 6 m at 70 germ. 70-40-70(43%)-40(28%) and 40(65%)-70(16%).
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Rhodotypos p. 205. 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 High Rated by us, not by the source.

Start around December 15, 2026 for a May 3 last frost.

  1. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

  2. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  3. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    16 germinated in this phase.

  4. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

    12 germinated in this phase.

Steps after step 2 run on after germination.

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

44% germination.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Rhodotypos p. 205Public domain
Show the original text
Rhodotypos (Rosaceae). A. tetrapetala gave multicycle germination with germination occurring at both 70 and 40.' Seeds collected in January germ. 70- 40(44%)-70(16%)-40(12%) and 40(14%)-70(24%)-40-70(14%)-40(11%)-70(3%). Seed DS 6 m at 40 germ. 70-40-70(47%)-40(25%) and 40(57%)-70(17%)-40-70(2%)- 40. Seed DS 6 m at 70 germ. 70-40-70(43%)-40(28%) and 40(65%)-70(16%).
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Rhodotypos p. 205. 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, 1993

Difficulty High Rated by us, not by the source.

Start around March 21, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on March 20, 2026.

  1. Dry storage

    Duration: 180 daysTemperature: 70°F 21°C

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

  3. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  4. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

  5. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

    28 germinated in this phase.

Steps after step 4 run on after germination.

about 12 months from start to step 4. Germination happens during step 4; time not stated, 21 days assumed.

43% germination.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Rhodotypos p. 205Public domain
Show the original text
Rhodotypos (Rosaceae). A. tetrapetala gave multicycle germination with germination occurring at both 70 and 40.' Seeds collected in January germ. 70- 40(44%)-70(16%)-40(12%) and 40(14%)-70(24%)-40-70(14%)-40(11%)-70(3%). Seed DS 6 m at 40 germ. 70-40-70(47%)-40(25%) and 40(57%)-70(17%)-40-70(2%)- 40. Seed DS 6 m at 70 germ. 70-40-70(43%)-40(28%) and 40(65%)-70(16%).
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Rhodotypos p. 205. 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, 1993

Difficulty 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

    14 germinated in this phase.

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

  3. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  4. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    14 germinated in this phase.

  5. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

    11 germinated in this phase.

  6. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    3 germinated in this phase.

Steps after step 2 run on after germination.

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

24% germination.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Rhodotypos p. 205Public domain
Show the original text
Rhodotypos (Rosaceae). A. tetrapetala gave multicycle germination with germination occurring at both 70 and 40.' Seeds collected in January germ. 70- 40(44%)-70(16%)-40(12%) and 40(14%)-70(24%)-40-70(14%)-40(11%)-70(3%). Seed DS 6 m at 40 germ. 70-40-70(47%)-40(25%) and 40(57%)-70(17%)-40-70(2%)- 40. Seed DS 6 m at 70 germ. 70-40-70(43%)-40(28%) and 40(65%)-70(16%).
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Rhodotypos p. 205. 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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