I am on the hunt for what to plant in my front doorside garden, which is a pie shaped, south facing sun trap. It is not a huge area, roughly 10" wide at the widest part of the pie, and about the same back to the middle of the pie arc to the back corner. I considered a Japanese Umbrella Pine, so beautiful, but am concerned at how fast it may overgrow the space. I would prefer something columnar, and that would top out at about 15'. And which is realistically available for purchase locally! Open to suggestions! many thanks, all for your help.