This source reports three treatments. All are shown.
Protocol 1
DerivedN. C. Deno, 1993Difficulty Moderate Rated by us, not by the source.
- 1
Sow outdoors and leave it
Up in April.
No stated waiting before sowing.
38% germination.
This source doesn't state how long.
Protocol 2
DerivedN. C. Deno, 1993Difficulty High Rated by us, not by the source.
Start around October 13, 2026 for a May 3 last frost.
- 1
Cold moist stratification
Duration: 90 days · Temperature: 40°F 4°C
- 2
Warm moist stratification
Duration: 90 days · Temperature: 70°F 21°C
1/8 germinated in this phase.
- 3
Cold moist stratification
Duration: 90 days · Temperature: 40°F 4°C
- 4
Warm moist stratification
Duration: 90 days · Temperature: 70°F 21°C
- 5
Cold moist stratification
Duration: 90 days · Temperature: 40°F 4°C
1/8 germinated in this phase.
Steps after step 1 run on after germination.
about 3 months from start to sowing. Then 84 days to germinate.
25% germination in 84 days.
Protocol 3
DerivedN. C. Deno, 1993Difficulty 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 days · Temperature: 70°F 21°C
- 2
Cold moist stratification
Duration: 90 days · Temperature: 40°F 4°C
- 3
Warm moist stratification
Duration: 90 days · Temperature: 70°F 21°C
- 4
Cold moist stratification
Duration: 90 days · Temperature: 40°F 4°C
- 5
Warm moist stratification
Duration: 90 days · Temperature: 70°F 21°C
Steps after step 1 run on after germination.
about 3 months from start to sowing. Then 21 days to germinate.
17% germination in 21 days.