Ask Mr. Smarty Plants

From Garden Adventures Nursery, here is an article on how this plant was developed for commercial use. Apparently the development of this plant began with a mutation on Chamaecyparis pisiflora 'Boulevard'.  We believe the 'Boulevard' is a trade name for Chamaecyparis pisiflora, which is native to Japan. When you have followed the trail of how this plant was developed, you will understand why there are so many factors involved, making it difficult to isolate a problem. Since the original plant is not native to North America, it falls out of our expertise at the Lady Bird Johnson Wildflower Center, where we specialize in the growth, propagation and protection of plants native not only to North America but to the areas in which the plants grow naturally.

In our Native Plant Database, there are two members of the genus Chamaecyparis, from which we might find some clues:

Chamaecyparis lawsoniana (Port orford cedar) - Native only to northern California and Oregon. 

Chamaecyparis thyoides (Atlantic white cedar) - This species thrives in a cool, moist atmosphere where it is protected from drying winds. It is relatively free of serious disease or insect problems and not susceptible to apple-cedar rust. It does not compete with hardwood species. It is native to North Carolina.

We did a little investigating into the climate of Wake County, in central North Carolina, and discovered it is humid and therefore could be considered acceptable to your plant. One possibility that occurs to us is transplant shock, which can show up in a transplanted plant for up to 3 years after it has been planted. Trimming of dead branches and checking for damage to the trunk are usually recommended.

We found a website, University of California Integrated Pest Management, on Pests and Diseases of Chamaecyparis. From eHow, here is an article on Chamaecyparis Diseases.