Going off of the previous question, Dahlias are u0022tender perennialsu0022. This means in some areas of the country they can grow back and in some they can't. In USDA zones 8 and above (throughout the Southern United States) Dahlias are considered perennials meaning that they naturally re-sprout each year. With the harsh winters that we face in the midwest and northern United States this is not possible and they will need to be re-planted each year. Plants that are considered perennials in our area of the country (zones 4/5) include, Lilies, Tulips, Daffodils, and Irises.