Before planting a container-grown shrub, gently knock it out of its pot to check to see if it has become root-bound. If your shrub is not root-bound, you may simply proceed to Step 7.
"Root-bound" just means that a thick mat of roots has built up on the outside of the rootball, due to the unnatural constraints imposed by the container. As a result, the roots can't pass nutrients to the shrub as they're supposed to. If you were to set the shrub in the ground in this state, the roots may not break free of this unnatural growing pattern.
There is a remedy. Although, if you were teased as a child, you may not like the sound of it....
The remedy is to "tease" the roots before planting. Fortunately, in the horticultural world, "teasing" doesn't have any negative connotations. Rather, it just means loosening the outer roots of the rootball, so that, once in the ground, the roots of a root-bound shrub can resume normal growth patterns again.
To loosen the roots of a root-bound plant, just run a sharp object (I used scissors) all along the exterior of the rootball, wherever the matting has occurred. You don't have to be fussy. The sharp object will cut into the matted areas, freeing the roots to grow naturally again. Don't worry about damaging the matted roots: they're useless in their current state.
Once ready to plant, I set each boxwood shrub in the middle of its planting hole, and begin to fill in around it -- the subject of Step 7....
