So why IS fall the very BEST time for planting? Two reasons: root growth and water availability.
Roots will continue to grow during warm fall days so when dry weather arrives next summer, the transplant already has established a few roots in it’s new home.
The number one cause of loss of newly planted plants is inadequate water. In eastern North Carolina, our soils usually are moist enough in winter to support most plants without having to give supplemental water. Deciduous plants need very little water in winter anyway since they have no leaves to transpire water. This does not mean that we don’t need to water newly-planted things in fall and winter. Always be sure to water any new transplant thoroughly to remove air pockets in the planting area. Also, broadleaved evergreens will loose water in winter and are especially vulnerable during long periods of cold when the ground my be frozen. Therefore, it is important to water newly transplanted broadleaved evergreens before a long-term hard freeze.