Cryptomeria japonica, commonly known as Japanese cedar or sugi, is a graceful evergreen conifer native to Japan and central/southern China. This important timber tree exhibits short dormancy that can be effectively broken with 2-3 weeks of cold stratification at 4°C. Seeds germinate within 3-9 weeks after stratification when maintained at warm temperatures around 15°C.
Before sowing
Short cold stratification (2-3 weeks) is essential to break dormancy. Keep seeds moist but not waterlogged during stratification.
Sowing
What to expect
Tips
Sow seeds 1/4 inch (6mm) deep and tamp soil lightly. Mulch the seed bed to maintain consistent moisture. Keep substrate moist but never waterlogged during germination. Ensure good air circulation to prevent damping off disease. Place seedlings in bright location after germination but shade from direct sun initially. Seedlings are robust and frost-hardy by 15-20 weeks; transplant to individual pots when large enough to handle. Germination requires patience—multiple winter cycles may occur naturally in cold climates.
Sources: PFAF Database, Forest Research UK, Tree Seed Online, Sheffield's Seeds, Forest Start
