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Clethra fargesii

Farges Clethra

Family ClethraceaeGenus Clethra

A long arching spike of white flowers with orange-tipped stamens, opening from pink buds
FlowerAgnieszka Kwiecień, NovaCC BY-SA 4.0

About the plant

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

The plant

Habit
ShrubExtension Gardener Plant Toolbox
Habit
shrub or treePlants of the World Online
Height
6-10 ft1.8-3 mExtension Gardener Plant Toolbox
Spread
3-6 ft0.9-1.8 mExtension Gardener Plant Toolbox
Flower
WhiteExtension Gardener Plant Toolbox
Blooms
SummerExtension Gardener Plant Toolbox
Native range
China South-Central, China SoutheastGBIF Backbone Taxonomy
Hardiness zones
5-7Extension Gardener Plant Toolbox

Growing conditions

Sun
Dappled Sunlight; Partial ShadeExtension Gardener Plant Toolbox
Soil
High Organic Matter, Loam (Silt)Extension Gardener Plant Toolbox
Soil pH
Acid (<6.0), Neutral (6.0-8.0)Extension Gardener Plant Toolbox
Moisture
Good Drainage, MoistExtension 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.

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

  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 77 days.

49% germination in 14–77 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Clethra p. 121Public domain
Show the original text
Clethra (Cletharaceae). Both species required light for germination. C. fargesli germ. 70L(15% in 2-11 w), 40-70L(49% in 2-11 w), and none in 70D, 70 GA-3, 40-70D, or outdoor treatment. A preliminary 6 w in 70D had no effect.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Clethra p. 121. 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 January 18, 2027 for a May 3 last frost.

  1. Sow and cover

    Temperature: 70°F 21°C Light: light

No stated waiting before sowing. Then 77 days to germinate.

15% germination in 14–77 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Clethra p. 121Public domain
Show the original text
Clethra (Cletharaceae). Both species required light for germination. C. fargesli germ. 70L(15% in 2-11 w), 40-70L(49% in 2-11 w), and none in 70D, 70 GA-3, 40-70D, or outdoor treatment. A preliminary 6 w in 70D had no effect.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Clethra p. 121. 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

  1. Sow and cover

    Temperature: 70°F 21°C Light: dark

No stated waiting before sowing.

0% germination.

Nothing germinated at 70.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Clethra p. 121Public domain
Show the original text
Clethra (Cletharaceae). Both species required light for germination. C. fargesli germ. 70L(15% in 2-11 w), 40-70L(49% in 2-11 w), and none in 70D, 70 GA-3, 40-70D, or outdoor treatment. A preliminary 6 w in 70D had no effect.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Clethra p. 121. Quoted exactly. Every value on this card comes from this record; the step names come from a fixed list.

Protocol 4

DerivedN. C. Deno, 1993

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

  1. Sow outdoors and leave it

    Nothing germinated outdoors.

No stated waiting before sowing.

0% germination.

This source doesn't state how long step 1 lasts.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Clethra p. 121Public domain
Show the original text
Clethra (Cletharaceae). Both species required light for germination. C. fargesli germ. 70L(15% in 2-11 w), 40-70L(49% in 2-11 w), and none in 70D, 70 GA-3, 40-70D, or outdoor treatment. A preliminary 6 w in 70D had no effect.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Clethra p. 121. 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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