Online plants recommends blue arrow as an excellent choice for a narrow pencil pine conifer.
As its name suggests, blue arrow is a thin, narrow, columnar shaped conifer. Blue arrow has been bred as an improved variety of skyrocket. It doesn't get the ugly nuts and keeps a much tighter and narrower form than skyrocket. Its also deeper blue in color.
Very slow growing form, after 10 years it will only have reached 3-4mt in height and 50cm in width. Very popular because of its steel blue foliage. Ideal as a medium height screen hedge, specimen planting with other conifers or consider using as an entrance plant in concrete pots. Mutch around the base to keep consistently moist during summer, this will keep the plant healthy and help with retaining the deep blue color.