Primula iljinskii
Genus Primula
This source reports three treatments. All are shown.
Protocol 1
DerivedN. C. Deno, 1993Difficulty Moderate Rated by us, not by the source.
Start around March 15, 2027 for a May 3 last frost.
- 1
Sow and cover
Temperature: 70°F 21°C · Light: light
No stated waiting before sowing. Then 21 days to germinate.
50% germination in 21 days.
Protocol 2
DerivedN. C. Deno, 1993Difficulty High Rated by us, not by the source.
Start around September 23, 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
about 6 months from start to sowing. Then 14 days to germinate.
12% germination in 14 days.
Protocol 3
DerivedN. C. Deno, 1993Difficulty Very high Rated by us, not by the source.
Start around December 22, 2026 for a May 3 last frost.
- 1
Warm moist stratification
Duration: 90 days · Temperature: 70°F 21°C · Light: dark
- 2
Cold moist stratification
Duration: 90 days · Temperature: 40°F 4°C
- 3
Warm moist stratification
Duration: 90 days · Temperature: 70°F 21°C · Light: dark
1/20 germinated in this phase.
Steps after step 1 run on after germination.
about 3 months from start to sowing. Then 14 days to germinate.
5% germination in 14 days.