Is it possible to grow rosemary in an outdoor bed in Nashville, Tennessee, without having to dig it up and bring it inside before the first frost? I am wondering whether heavy mulching at the base and a burlap cover over the plant would help it live through our mild winter freezes.
Since rosemary is a tender shrub that overwinters well in Zones 8 through 10 and Nashville is in Zone 6, you’ll be taking a risk by leaving yours outside through the cold season. But it’s worth a shot. Mulching heavily is a good idea — try surrounding the plant with leaves packed into black plastic bags — and consider building a cold frame for the plant. Also, if you can, put the plant on the south side of your house, up against a wall for protection, but in full sun. This may provide enough warmth to help the plant survive the winter.