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Gardenia jasminoides

Cape Jasmine · Cape-jessamine · Gargenia

Family RubiaceaeGenus Gardenia

A rounded shrub covered in white flowers with yellow centers among glossy dark leaves
The whole plantAlpsdakeCC 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
4-8 ft1.2-2.4 mExtension Gardener Plant Toolbox
Spread
4-8 ft1.2-2.4 mExtension Gardener Plant Toolbox
Flower
Cream/Tan, Gold/Yellow, WhiteExtension Gardener Plant Toolbox
Blooms
Spring, SummerExtension Gardener Plant Toolbox
Native range
Cambodia, China North-Central, China South-Central, China Southeast, East Himalaya, Hainan and elsewhereGBIF Backbone Taxonomy
Hardiness zones
7-11Extension Gardener Plant Toolbox

Growing conditions

Sun
Dappled Sunlight; Full sun; Partial ShadeExtension Gardener Plant Toolbox
Soil
Clay, High Organic Matter, Loam (Silt), SandExtension Gardener Plant Toolbox
Soil pH
Acid (<6.0)Extension Gardener Plant Toolbox
Moisture
Good Drainage, Moist, Occasionally Dry, Occasionally WetExtension 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

  • Grown in China since at least the Song dynasty (960–1279), where it was painted by the emperor Huizong. John Ellis named Gardenia in 1761 after the Scottish naturalist Alexander Garden. Wikipedia: Gardenia jasminoides
  • The flowers can be eaten raw, pickled or preserved in honey. In China the petals scent tea, and a yellow-red dye for textiles and sweets has been extracted from the fruit pulp. Wikipedia: Gardenia jasminoides

This source reports two treatments. Both are shown.

Protocol 1

DerivedN. C. Deno, 1996

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. Germination time not stated; 21 days assumed.

90% germination.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Gardenia p. 45Public domain
Show the original text
Gardenia (Rubiaceae). G. jasminoides germ. 70D(90% in 3rd ) w confirrmr^a past report (JH). This dropped to 70D(20% in 3rd w)7o s^ds DS 1 y 3rd w ) , ^^ ^ 2-4 w), 70L(85^in
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Gardenia p. 45. 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, 1996

Difficulty High Rated by us, not by the source.

Start around March 16, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on March 15, 2026.

  1. Dry storage

    Duration: 365 daysTemperature: 70°F 21°C

  2. Sow and cover

    Temperature: 70°F 21°C Light: dark

about 12 months from start to sowing. Then 21 days to germinate.

20% germination in 21 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Gardenia p. 45Public domain
Show the original text
Gardenia (Rubiaceae). G. jasminoides germ. 70D(90% in 3rd ) w confirrmr^a past report (JH). This dropped to 70D(20% in 3rd w)7o s^ds DS 1 y 3rd w ) , ^^ ^ 2-4 w), 70L(85^in
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Gardenia p. 45. 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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