Plant the Shrub
Remove the shrub from the pot and inspect the root ball (Image 1). Typically the root growth will have been compressed by growth inside the pot. If the shrub is rootbound, use a sharp implement, such as a trowel, knife or pruners, to divide and loosen the roots (Image 2). Once you've loosened the roots, place the root ball into the hole (Image 3). Plant the shrub so that the top of the root ball is level with the surrounding soil. Fill the hole with the loosened native soil that was removed from the hole. Firmly but gently press the soil in place; take care not to pack the soil or the roots may have difficulty growing and penetrating the soil.
Note: Experts used to recommend adding soil amendments when planting trees, but research proves that it's better not to improve the soil. Rich soil in the planting hole discourages roots from venturing into the leaner surrounding soil and becoming well anchored. Simply fill the hole in with the native soil, and pack it down lightly to get rid of air pockets.