[bharada]

Trimming it like a hedge will cause it to grow like a hedge, very dense and compact. I tried this method for a couple of months, but unless you're extremely diligent at it, the undergrowth will start to yellow leaving you with an unsightly hedge for a week after a trim (until the new growth starts to fill in again).

I belive it was Roger Miller who said he prefers to maintain his by plucking stems out, which would do a better job of maintaining a more natural shape. It also lets more light into the stand reducing the yellowing in the undergrowth.