Black Walnut (Juglans nigra) is a valuable deciduous hardwood tree native to eastern North America, prized for its timber and edible nuts. Seeds have deep physiological dormancy and require cold-moist stratification for 90-120 days to break dormancy and achieve successful germination. The species exhibits shade intolerance and prefers full sun conditions for optimal growth.
Before sowing
Remove husk and perform float test; viable seeds sink while non-viable seeds float. Mix with moist sand or peat moss before stratification.
Sowing
What to expect
Tips
Collect nuts after they naturally fall from the tree in late September to October; remove husks carefully using gloves as they contain dye. Plant 90-120 days stratified seeds approximately 1 inch deep in spring after last frost. Maintain consistent moisture but avoid waterlogging. Germination typically occurs within 2-4 weeks after proper stratification. Protect young seedlings from rodent damage. Note: germination is variable and sensitive to seed source; plant more seeds than needed. Seedlings have a deep taproot and should be transplanted carefully or direct-seeded to permanent location.
Sources: USDA Forest Service Silvics, NC State Extension, University of Kentucky Horticulture, Forest Research (UK), Wikipedia, Sacred Plant Co., Living Soil Tree Farm, ProGardenTips
