Deno’s Garden

Koelreuteria paniculata

Golden Rain Tree · Pride of India · Panicled Goldenrain Tree · Golden-Rain Tree

Family SapindaceaeGenus Koelreuteria

A spreading tree carrying yellow flower panicles and pink seed capsules
The whole plantDidier DescouensCC BY-SA 4.0

About the plant

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

The plant

Habit
TreePlant Finder
Habit
Perennial, TreePLANTS Database
Height
30-40 ftPlant Finder
Height
45.0 ftPLANTS Database
Spread
30-40 ftPlant Finder
Flower
Showy; yellowPlant Finder
Flower
YellowPLANTS Database
Blooms
June to JulyPlant Finder
Blooms
Late SpringPLANTS Database
Native range
North AmericaGBIF Backbone Taxonomy
Native range
Northern China, Korea, JapanPlant Finder
Hardiness zones
5-9Plant Finder
Note
Deno reads the seed coat as impervious, and dry storage as working by opening microfissures.Seed Germination Theory and Practice, 2nd ed.
Note
Tolerates drought, clay and city air. Good autumn leaf colour and showy fruit.Plant Finder

Growing conditions

Sun
Full sunPlant Finder
Sun
Shade tolerance: HighPLANTS Database
Soil
Average, dry to medium, well-drainedPlant Finder
Moisture
Dry to mediumPlant Finder
Moisture
Moisture use: MediumPLANTS Database
Watering
Dry to 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; GBIF Backbone Taxonomy — Global Biodiversity Information Facility; Seed Germination Theory and Practice, 2nd ed. — N. C. Deno.

This source reports 7 treatments. All are shown.

Protocol 1

DerivedN. C. Deno, 1993

Difficulty Low Rated by us, not by the source.

Start around April 15, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on April 14, 2026.

  1. Dry storage

    Duration: 180 daysTemperature: 40°F 4°C

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    Deno gives no length for this period; three months is his standard cycle.

  3. Cold moist stratification

    Duration: 84 daysTemperature: 40°F 4°C

    Seeds start splitting near the end of the 12th week; some radicles emerge here.

  4. Warm moist stratification

    Temperature: 70°F 21°C

    The radicle grows rapidly once it is back at 70.

about 12 months from start to sowing. Then 2 days to germinate.

90% germination in 1–2 days.

The best run in the entry: six months dry at 40, then the standard cycle.

This source doesn't state how long.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, KoelreuteriaPublic domain
Show the original text
Koelreuteria (Sapindaceae). K. paniculata is primarily a 70-40-70 germinator. However, near the end of the cycle at 40 (in the 12th w) splitting of the seeds starts and the radicle may emerge and grow a few millimeters. When such seeds are shifted to 70, the radicle grows rapidly. For simplicity the seeds were counted as germ. after the shift to 70. Germination was best with DS seed as shown by 70(10%)-40-70(85% in 1-2 d) for seed DS 6 m at 70, 70-40-70(90% in 1-2 d) for seed DS6 m at 40, and only 70(2%)-40-70(49%) for fresh seed. Seeds can be DS for 12 and 18 m with only a small decline in percent germination as shown by 70-40-70(68%) for seed DS 12 m at 70 and 70-40-70(69%) for seed DS 18 m at 70. A preliminary 3m at 40 had no effect. Seeds in which a hole had been produced in the seed coat germ. 70(29%) and 40(40%) suggesting that the seed coat is impervious and delays water transport which delays germination, but the effect is not as dramatic as in many of the species discussed in Chapter 9. The effect of the hole in the seed coat also indicates that the favorable effect of DS may be to open microfissures.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Koelreuteria. 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 April 15, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on April 14, 2026.

  1. Dry storage

    Duration: 180 daysTemperature: 70°F 21°C

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    10% germinated here. Deno gives no length for this period; three months is his standard cycle.

  3. Cold moist stratification

    Duration: 84 daysTemperature: 40°F 4°C

    Seeds start splitting near the end of the 12th week; some radicles emerge here.

  4. Warm moist stratification

    Temperature: 70°F 21°C

    The radicle grows rapidly once it is back at 70.

about 12 months from start to sowing. Then 2 days to germinate.

85% germination in 1–2 days.

Six months dry at 70 first. A tenth comes up in the opening warm period.

This source doesn't state how long.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, KoelreuteriaPublic domain
Show the original text
Koelreuteria (Sapindaceae). K. paniculata is primarily a 70-40-70 germinator. However, near the end of the cycle at 40 (in the 12th w) splitting of the seeds starts and the radicle may emerge and grow a few millimeters. When such seeds are shifted to 70, the radicle grows rapidly. For simplicity the seeds were counted as germ. after the shift to 70. Germination was best with DS seed as shown by 70(10%)-40-70(85% in 1-2 d) for seed DS 6 m at 70, 70-40-70(90% in 1-2 d) for seed DS6 m at 40, and only 70(2%)-40-70(49%) for fresh seed. Seeds can be DS for 12 and 18 m with only a small decline in percent germination as shown by 70-40-70(68%) for seed DS 12 m at 70 and 70-40-70(69%) for seed DS 18 m at 70. A preliminary 3m at 40 had no effect. Seeds in which a hole had been produced in the seed coat germ. 70(29%) and 40(40%) suggesting that the seed coat is impervious and delays water transport which delays germination, but the effect is not as dramatic as in many of the species discussed in Chapter 9. The effect of the hole in the seed coat also indicates that the favorable effect of DS may be to open microfissures.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Koelreuteria. 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 April 1, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on March 31, 2025.

  1. Dry storage

    Duration: 540 daysTemperature: 70°F 21°C

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    Deno gives no length for this period; three months is his standard cycle.

  3. Cold moist stratification

    Duration: 84 daysTemperature: 40°F 4°C

    Seeds start splitting near the end of the 12th week; some radicles emerge here.

  4. Warm moist stratification

    Temperature: 70°F 21°C

    The radicle grows rapidly once it is back at 70.

about 2 years from start to sowing. Germination time not stated; 21 days assumed.

69% germination.

Eighteen months dry is no worse than twelve.

This source doesn't state how long.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, KoelreuteriaPublic domain
Show the original text
Koelreuteria (Sapindaceae). K. paniculata is primarily a 70-40-70 germinator. However, near the end of the cycle at 40 (in the 12th w) splitting of the seeds starts and the radicle may emerge and grow a few millimeters. When such seeds are shifted to 70, the radicle grows rapidly. For simplicity the seeds were counted as germ. after the shift to 70. Germination was best with DS seed as shown by 70(10%)-40-70(85% in 1-2 d) for seed DS 6 m at 70, 70-40-70(90% in 1-2 d) for seed DS6 m at 40, and only 70(2%)-40-70(49%) for fresh seed. Seeds can be DS for 12 and 18 m with only a small decline in percent germination as shown by 70-40-70(68%) for seed DS 12 m at 70 and 70-40-70(69%) for seed DS 18 m at 70. A preliminary 3m at 40 had no effect. Seeds in which a hole had been produced in the seed coat germ. 70(29%) and 40(40%) suggesting that the seed coat is impervious and delays water transport which delays germination, but the effect is not as dramatic as in many of the species discussed in Chapter 9. The effect of the hole in the seed coat also indicates that the favorable effect of DS may be to open microfissures.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Koelreuteria. 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 Low Rated by us, not by the source.

Start around September 28, 2026 for a May 3 last frost. Too late for spring 2027 — that needed starting on September 27, 2025.

  1. Dry storage

    Duration: 360 daysTemperature: 70°F 21°C

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    Deno gives no length for this period; three months is his standard cycle.

  3. Cold moist stratification

    Duration: 84 daysTemperature: 40°F 4°C

    Seeds start splitting near the end of the 12th week; some radicles emerge here.

  4. Warm moist stratification

    Temperature: 70°F 21°C

    The radicle grows rapidly once it is back at 70.

about 18 months from start to sowing. Germination time not stated; 21 days assumed.

68% germination.

A year in dry storage costs surprisingly little.

This source doesn't state how long.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, KoelreuteriaPublic domain
Show the original text
Koelreuteria (Sapindaceae). K. paniculata is primarily a 70-40-70 germinator. However, near the end of the cycle at 40 (in the 12th w) splitting of the seeds starts and the radicle may emerge and grow a few millimeters. When such seeds are shifted to 70, the radicle grows rapidly. For simplicity the seeds were counted as germ. after the shift to 70. Germination was best with DS seed as shown by 70(10%)-40-70(85% in 1-2 d) for seed DS 6 m at 70, 70-40-70(90% in 1-2 d) for seed DS6 m at 40, and only 70(2%)-40-70(49%) for fresh seed. Seeds can be DS for 12 and 18 m with only a small decline in percent germination as shown by 70-40-70(68%) for seed DS 12 m at 70 and 70-40-70(69%) for seed DS 18 m at 70. A preliminary 3m at 40 had no effect. Seeds in which a hole had been produced in the seed coat germ. 70(29%) and 40(40%) suggesting that the seed coat is impervious and delays water transport which delays germination, but the effect is not as dramatic as in many of the species discussed in Chapter 9. The effect of the hole in the seed coat also indicates that the favorable effect of DS may be to open microfissures.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Koelreuteria. 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 Moderate Rated by us, not by the source.

Start around September 22, 2026 for a May 3 last frost.

  1. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    2% germinated here. Deno gives no length for this period; three months is his standard cycle.

  2. Cold moist stratification

    Duration: 84 daysTemperature: 40°F 4°C

    Seeds start splitting near the end of the 12th week; some radicles emerge here.

  3. Warm moist stratification

    Temperature: 70°F 21°C

    The radicle grows rapidly once it is back at 70.

about 6 months from start to sowing. Germination time not stated; 21 days assumed.

49% germination.

Fresh seed gives about half what dry-stored seed gives. A preliminary 3 m at 40 made no difference.

This source doesn't state how long.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, KoelreuteriaPublic domain
Show the original text
Koelreuteria (Sapindaceae). K. paniculata is primarily a 70-40-70 germinator. However, near the end of the cycle at 40 (in the 12th w) splitting of the seeds starts and the radicle may emerge and grow a few millimeters. When such seeds are shifted to 70, the radicle grows rapidly. For simplicity the seeds were counted as germ. after the shift to 70. Germination was best with DS seed as shown by 70(10%)-40-70(85% in 1-2 d) for seed DS 6 m at 70, 70-40-70(90% in 1-2 d) for seed DS6 m at 40, and only 70(2%)-40-70(49%) for fresh seed. Seeds can be DS for 12 and 18 m with only a small decline in percent germination as shown by 70-40-70(68%) for seed DS 12 m at 70 and 70-40-70(69%) for seed DS 18 m at 70. A preliminary 3m at 40 had no effect. Seeds in which a hole had been produced in the seed coat germ. 70(29%) and 40(40%) suggesting that the seed coat is impervious and delays water transport which delays germination, but the effect is not as dramatic as in many of the species discussed in Chapter 9. The effect of the hole in the seed coat also indicates that the favorable effect of DS may be to open microfissures.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Koelreuteria. 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 Moderate Rated by us, not by the source.

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

  1. Nick or sand the seed coat

    A hole produced in the seed coat.

  2. Cold moist stratification

    Temperature: 40°F 4°C

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

40% germination.

With a hole in the coat the seed will even germinate at 40, which it otherwise will not.

This source doesn't state how long.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, KoelreuteriaPublic domain
Show the original text
Koelreuteria (Sapindaceae). K. paniculata is primarily a 70-40-70 germinator. However, near the end of the cycle at 40 (in the 12th w) splitting of the seeds starts and the radicle may emerge and grow a few millimeters. When such seeds are shifted to 70, the radicle grows rapidly. For simplicity the seeds were counted as germ. after the shift to 70. Germination was best with DS seed as shown by 70(10%)-40-70(85% in 1-2 d) for seed DS 6 m at 70, 70-40-70(90% in 1-2 d) for seed DS6 m at 40, and only 70(2%)-40-70(49%) for fresh seed. Seeds can be DS for 12 and 18 m with only a small decline in percent germination as shown by 70-40-70(68%) for seed DS 12 m at 70 and 70-40-70(69%) for seed DS 18 m at 70. A preliminary 3m at 40 had no effect. Seeds in which a hole had been produced in the seed coat germ. 70(29%) and 40(40%) suggesting that the seed coat is impervious and delays water transport which delays germination, but the effect is not as dramatic as in many of the species discussed in Chapter 9. The effect of the hole in the seed coat also indicates that the favorable effect of DS may be to open microfissures.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Koelreuteria. 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 7

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. Nick or sand the seed coat

    A hole produced in the seed coat.

  2. Sow and cover

    Temperature: 70°F 21°C

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

29% germination.

A hole in the coat skips the whole cycle, at a cost: 29% instead of 85%.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, KoelreuteriaPublic domain
Show the original text
Koelreuteria (Sapindaceae). K. paniculata is primarily a 70-40-70 germinator. However, near the end of the cycle at 40 (in the 12th w) splitting of the seeds starts and the radicle may emerge and grow a few millimeters. When such seeds are shifted to 70, the radicle grows rapidly. For simplicity the seeds were counted as germ. after the shift to 70. Germination was best with DS seed as shown by 70(10%)-40-70(85% in 1-2 d) for seed DS 6 m at 70, 70-40-70(90% in 1-2 d) for seed DS6 m at 40, and only 70(2%)-40-70(49%) for fresh seed. Seeds can be DS for 12 and 18 m with only a small decline in percent germination as shown by 70-40-70(68%) for seed DS 12 m at 70 and 70-40-70(69%) for seed DS 18 m at 70. A preliminary 3m at 40 had no effect. Seeds in which a hole had been produced in the seed coat germ. 70(29%) and 40(40%) suggesting that the seed coat is impervious and delays water transport which delays germination, but the effect is not as dramatic as in many of the species discussed in Chapter 9. The effect of the hole in the seed coat also indicates that the favorable effect of DS may be to open microfissures.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Koelreuteria. 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.