Answer: I think Green Tower Boxwood would be the perfect plant for your hedge. Just 2 feet wide but reaching 9 feet tall, this columnar evergreen offers year-round beauty with almost no effort on your part. The habit of this plant is very dense, yet it keeps its neat, straight-up-and-down shape, as if you'd just finished shearing it. In fact, you never have to do a thing to the foliage, but if you want to shape it, Green Tower is dense enough to create topiary without leaving unsightly gaps and holes. The foliage is medium- to fine-textured, giving Green Tower a full, solid look even from a young age.
You might also consider Escallonia, which is wider than Green Tower, but produces flowers throughout the summer, or California Lilac.
Best wishes with your landscape!
Q&A Library Searching Tips