I've planted several varieties of miscanthus and pennisetum this year and they have yet to take off & grow much. I also have some pennisetum 'little bunny' from last year that is even slower than the newer plants. I haven't had much prior experience with grasses (except for a zebra grass planted 3-4 years ago). Is this due to our recent cooler weather, or what? They are in full sun, and I added a slow-release granular fertilizer when I planted them in early April. I guess I'm impatient.