In nature, Black Walnut and Butternut trees appear along the edges of forests and hedgerows. Here they get the light and space they need to thrive. They, along with the English Walnut, prefer moist, well-drained loamy soil that is neutral or a bit on the alkaline side (pH 6.6 to 8.0). They have no tolerance for light, poor soils typical of urban sites. Like most trees, they prefer full sun, but they will tolerate light shade.
Plant Walnuts in the spring. These trees are notoriously difficult to transplant because they have long taproots, so it is best to choose young trees that are either in containers or have their roots in a soil ball wrapped in burlap. The best planting size is 5 to 10 feet. Keep the roots moist until planting time.