It's the end of February and I decided to go ahead and cut back my switchgrass to about 10 inches. We've already cut back the grasses at work but I work in midtown which is USDA hardiness zone 8a and Alpharetta/Milton is zone 7b so I put off doing it until closer to March.
When cutting back ornamental grasses, just remember that the clump of old grass that you leave will do the work of protecting the new growth that is pushing up. After all, this is north Georgia and we are famous for early spring freezes that seem to always follow days of 70-degree weather!
As you can see from the photo above, my canine horticultural assistant, Chester, is trying to, eh-hem, assist.