Pampas Grasses

I have always loved Pampas Grasses and was pleased when we moved to our present house that we had a big enough garden to accommodate them. I don't know why, maybe something to do with their feathery texture. What I find surprising, however, is the fact that they bloom in the autumn/winter months and then die off in the spring/summer a sort of reversed seasonality to all of the other plants and I am not quite sure why this should be so.