Suitable for...
Grasses from cool climates (such as Carex, Calamagrostis, Chasmanthium, Deschampsia, Festuca, Hakonechloa, Helictotrichon, Molinia and Stipa) require frequent division, perhaps every three years, to prevent root congestion and loss of vigour.
Grasses from warm climates (such as Arundo, Cortaderia, Imperata, Miscanthus, Panicum, Pennisetum, Phalaris and Spartina) require only infrequent division.