How can I germinate walnuts?
Collect walnuts after they fall to the ground. Remove the husks, then place the nuts in water. The nuts that float are not viable and can be discarded. Good, viable nuts will sink to the bottom.
Before walnuts will germinate, the nuts need to be exposed to cold temperatures and moist conditions. The cold-moist requirement can be met by planting the nuts in the ground in fall. Plant walnuts 1 to 2 inches deep.
The cold-moist requirement can also be accomplished through a process called stratification. Walnuts can be stratified by placing the nuts in a moist mixture of sand and sphagnum peat moss and then storing them in a cool location. Suitable containers include coffee cans, plastic buckets, and food storage bags. The refrigerator is a good storage location. (Stratification temperatures should be just above freezing.) The walnuts must remain in the refrigerator for 90 to 120 days. After the nuts have been properly stratified, they can be removed from the refrigerator and planted.