I have a friend who uses this as a hedge around her hot tub (hey, this IS the CA forum) and she shears it regularly to about 3' so I have no idea how wide it wants to go if left unchecked. I had about 3-4 plants in a shallow planter box for about 5 years or so and they never got beyond about 2-3' wide but the container likely had a controlling effect. They make a nice hedge as the small leaves are glossy and a very nice shade of bright green. They recover from the shearing very quickly and never seem to end up with those woody patches that you sometimes see with hollies, for example.