Years ago I bought 2 little rosemary plants on clearance after Christmas from Walmart. I kept them inside for about a year but then planted them outside the following spring. One died but the other one is doing good. Here in the armpit of Arkansas Our Winters are usually not that bad. We do get rain that turns into ice but usually no snow. I think the first year or two I would cover my plants with an old blanket but after that I would forget.