Trillium grandiflorum
Genus Trillium
About the plant
What it is and where it grows — not part of any germination protocol.
- Habit
- Perennial, Forb/herb
- Native range
- Canada, lower 48 states
Toxicity is noted only where a source states it. No note here is not a finding of safety.
Source: PLANTS Database — USDA NRCS.
Two sources report 4 treatments between them. All are shown.
Protocol 1
DerivedN. C. Deno, 1998Difficulty Moderate Rated by us, not by the source.
Start around August 13, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on August 12, 2026.
- 1
Cold moist stratification
Duration: 90 days · Temperature: 40°F 4°C
- 2
Warm moist stratification
Duration: 90 days · Temperature: 70°F 21°C
about 6 months from start to sowing. Then 56 days to germinate.
80% germination in 56 days.
Protocol 2
DerivedN. C. Deno, 1993Difficulty High Rated by us, not by the source.
Start around September 17, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on September 16, 2026.
- 1
Cold moist stratification
Duration: 90 days · Temperature: 40°F 4°C
- 2
Warm moist stratification
Duration: 90 days · Temperature: 70°F 21°C
- 3
Cold moist stratification
Duration: 90 days · Temperature: 40°F 4°C
31 germinated in this phase.
Steps after step 2 run on after germination.
about 6 months from start to sowing. Germination time not stated; 21 days assumed.
42% germination.
Protocol 3
DerivedN. C. Deno, 1993Difficulty Low Rated by us, not by the source.
Start around January 18, 2027 for a May 3 last frost.
- 1
- 2
Sow and cover
Temperature: 70°F 21°C
No stated waiting before sowing. Then 77 days to germinate.
74% germination in 49–77 days.
Protocol 4
DerivedN. C. Deno, 1993Difficulty High Rated by us, not by the source.
Start around December 21, 2026 for a May 3 last frost. Too late for spring 2027 — that needed starting on December 20, 2025.
- 1
Warm moist stratification
Duration: 90 days · Temperature: 70°F 21°C
22 germinated in this phase.
- 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
- 6
Cold moist stratification
Duration: 90 days · Temperature: 40°F 4°C
3 germinated in this phase.
Steps after step 5 run on after germination.
about 15 months from start to sowing. Germination time not stated; 21 days assumed.
24% germination.