Sequoiadendron giganteum, the giant sequoia, is the world's largest tree by volume and is endemic to the Sierra Nevada mountains of California. These seeds have moderate dormancy and require cold stratification to achieve optimal germination rates of 20-73% depending on technique. Seeds demonstrate photoblastic responses requiring light for germination and must be sown very near the soil surface for success.
Before sowing
Leach seeds in running water for 24 hours, surface-dry, then cold stratify in sealed plastic bags without medium for optimal results.
Sowing
What to expect
Tips
Surface sow seeds (no deeper than 1/8 inch) and keep soil consistently moist but not waterlogged. Use bottom-watering or fine mist to avoid displacing tiny seeds. Provide 12-16 hours of bright indirect light daily. Ensure excellent air circulation to prevent damping-off fungal disease, which is the primary cause of seedling mortality. After stratification, germination typically occurs within 7-21 days. Seedlings are highly susceptible to damping-off in the critical first 3-6 months, so maintain good drainage and avoid wetting foliage.
Sources: California State Parks, US Forest Service FEIS, USDA Silvics, Superlative Trees research, Sacred Plant Co germination studies
