We live in Michigan and we have pampas grass. We cut the plant down in the early spring, but leaving about 5 inches above the ground of the dried canes. Our grass grows only on the outside of the clump. Are we doing something wrong, or is this the natural habit.
The inner core dies out. You will need to dig it up and divide the plant next spring. It is a whale of a task, in my experience. Once it is out of the ground, pitch the dead core and select outer sections to replant. If you do this every 3 years, it isn't that bad a task but if the grass is, say, 10 years without dividing, you are in for some work!