Fertile, well-drained soil.
Full sun or partial shade.
Yes, but flowers can be damaged by late frosts.
Mulch with well-rotted organic matter in spring.
Persimmon. Can restrict growth in other plants nearby, because many plants (including tomatoes) are sensitive to juglone, a substance present in walnut roots, leaves and wood. Walnuts should be grown in an orchard of their own, far from the vegetable garden.
Single Plants: 65′ 7″ (20.00m) each way (minimum)
Rows: 65′ 7″ (20.00m) with 65′ 7″ (20.00m) row gap (minimum)
Sow and Plant
Prepare a large hole by breaking up the soil and adding plenty of well-rotted organic matter. A wide hole is better than a very deep one. Mulch after planting, and encircle the trunk with a wire cage or protective pipe to protect the young tree from animal and insect pests.
Healthy walnut trees will bear for many decades.
Knock down nuts when ripe, remove the peel and dry. If pickling, harvest while it is still possible to pierce the nuts with a skewer.
Native black walnuts are often easier to grow in the US compared to English or Persian walnuts.