Generally, the distance between planting boxwood shrubs should be 1 to 3 feet, depending on the type and the look you want. If you want a very thick hedge, then plant them closer, about 1 to 1. 5 feet apart, so that they will quickly fill in. If you want individual plants or a more natural look, then space them 2 to 3 feet apart to ensure good air circulation and growth. Also, look at the typical mature width of the specific type of boxwood you want, as some species are wider than others. Good spacing not only helps to prevent diseases but also gives you healthy, well-shaped shrubs in the long run.