Mendel’s Gardens

Forsythia suspensa

Weeping Forsythia · Golden Bell Tree

Family OleaceaeGenus Forsythia

About the plant

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

The plant

Habit
Deciduous shrubPlant Finder
Habit
Perennial, ShrubPLANTS Database
Height
6-10 ftPlant Finder
Height
6.0 ftPLANTS Database
Spread
6-10 ftPlant Finder
Flower
Showy; yellowPlant Finder
Flower
YellowPLANTS Database
Blooms
March to AprilPlant Finder
Blooms
Early SpringPLANTS Database
Native range
ChinaPlant Finder
Hardiness zones
5-8Plant Finder

Growing conditions

Sun
Full sun to part shadePlant Finder
Sun
Shade tolerance: HighPLANTS Database
Moisture
Moisture use: MediumPLANTS Database
Watering
MediumPlant Finder

Toxicity is noted only where a source states it. No note here is not a finding of safety.

Sources: Plant Finder — Missouri Botanical Garden; PLANTS Database — USDA NRCS.

This source reports two treatments. Both are shown.

Protocol 1

DerivedN. C. Deno, 1993

Difficulty Moderate Rated by us, not by the source.

Start around March 15, 2027 for a May 3 last frost.

  1. Warm moist stratification

    Temperature: 70°F 21°C

    10% germinated at 70 before the cold period.

  2. Cold moist stratification

    Temperature: 40°F 4°C

  3. Warm moist stratification

    Temperature: 70°F 21°C

    A further 20% after the cold period.

No stated waiting before sowing. Germination time not stated; 21 days assumed.

10% germination.

A tenth comes up before the cold period and a fifth more after it.

This source doesn't state how long.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, ForsythiaPublic domain
Show the original text
Forsythia (Oleaceae). F. suspensa germ. 70(10%)-40-70(20%) and 40-70(10%).
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Forsythia. 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 Moderate Rated by us, not by the source.

Start around March 15, 2027 for a May 3 last frost.

  1. Cold moist stratification

    Temperature: 40°F 4°C

  2. Warm moist stratification

    Temperature: 70°F 21°C

No stated waiting before sowing. Germination time not stated; 21 days assumed.

10% germination.

This source doesn't state how long.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, ForsythiaPublic domain
Show the original text
Forsythia (Oleaceae). F. suspensa germ. 70(10%)-40-70(20%) and 40-70(10%).
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Forsythia. 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.