This source reports three treatments. All are shown.
Protocol 1
DerivedN. C. Deno, 1993Difficulty High Rated by us, not by the source.
Start around March 15, 2027 for a May 3 last frost.
- 1
- 2
Sow and cover
Temperature: 70°F 21°C · Light: dark
No stated waiting before sowing. Then 21 days to germinate.
33% germination in 21 days.
GA-3 raises the germination but the seedlings soon rotted.
Protocol 2
DerivedN. C. Deno, 1993Difficulty High Rated by us, not by the source.
Start around February 22, 2027 for a May 3 last frost.
- 1
Sow and cover
Temperature: 70°F 21°C · Light: dark
No stated waiting before sowing. Then 42 days to germinate.
25% germination in 42 days.
Protocol 3
DerivedN. C. Deno, 1993Difficulty High Rated by us, not by the source.
Start around December 1, 2026 for a May 3 last frost.
- 1
Cold moist stratification
Duration: 90 days · Temperature: 40°F 4°C
- 2
Sow and cover
Temperature: 70°F 21°C · Light: dark
about 3 months from start to sowing. Then 35 days to germinate.
22% germination in 35 days.