If you don't have Rosemary growing at your house yet, it should be easy to find young plants at your local garden center right now. Rosemary is one of my favorite plants to grow, as well as a favorite herb; we love it so much we named our dog Rosemary!
They are easy to grow and thrive in full sun. They tolerate humidity better than many other herbs, as they are used to growing near the sea. A Rosemary bush will grow as tall as man, but not taller, according to a legend that centers around Christ. This particular bush has been growing for us for four years now, and it was a couple or more years old when we bought it in a large pot; this is the first year that it has completely flowered. We had small smatterings of blooms over the last two years, but this year it has blooms covering the whole bush. Even if you don't have a garden, you ought to grow a Rosemary. They will do well in pots outdoors, as long as they have plenty of room for their roots. If your temps go down below 0, not just freezing, then you will want to grow it in a pot and bring it inside or somewhere protected to overwinter. On the Gulf Coast, where we live, they are hardy and stay green all year.
Once you get some, besides cooking with it (it's particularly good with chicken, green beans, or potatoes), you can also use it to make things like flea dip for your dog, hair rinses for extra shine, and skin cleansing products. Here is my recipe for facial toner/ astringent made with this herb and strawberry leaves.