It won't be long before it grows big. More of an upright bush. When the flower is ready to be cut off, just take it down to the end of the peduncle. It's a little fussy if cut down too much. I've been growing this beauty since 1991. My 2 bush's are direct decedents from that bush. Once it matures, take some cutting, It is fairly easy to propagate.

Thank you Ken. That helps to know where to make the cut for deadheading. I had a feeling it could get big