The one on the right of the sidewalk has a few in it and the one on the left is new and I'm just getting ready to fill. This was from winter storage prep in November. The larger garden area is usually vegies but it has a temporary boxwood and fur just out of sight.
The area left of the flagstone has a Hemlock holly, dogwood, Laceleaf JMaple and a juniper but plans for more J Mapel if the cuttings take I'm working. I have about a five foot strip empty for those.
I most prefer them in containers as working on the ground sux. LOL
It can be either, but if you have the trees in the ground without any way to constrain the root systems, you either need to space your trees out about ten-fold or end up with a 6 foot by 12 foot forest planting. When they are in a grow bag or pond basket or pot you can fit in about ten times as many trees...and less digging.