I take the large clumps apart, send them to new homes and replant just a few from the clump. Fall is a good time for me to do that, then they will have room next spring when they take off growing again. Many of them are such heavy producers of offsets. This also helps with air flow around the rosettes so they won't rot during our rainy season.
This year I had several that attained just short of 12" across the main rosette.
