ORGHPS Germination Guide: Sow immediately, Either the viability of these seeds is short or the species propagates best with fresh seed. Stored seed might be coaxed into germination with temperature cycling and patience. Expose to fluctuation outdoor winter temperatures including freezing for 3 months. Gradually increase light and temperature in the spring. * Clothier recommends 25°C x 4 weeks then 4°C (dark) x 12 weeks, slowly raise temp and light, grow seedlings at 4°C

Source: Ontario Rock Garden & Hardy Plant Society