Answer: Annuals are plants that grow, flower, set seeds and then die. There are cool season annuals and warm season annuals. Each will need to be replaced at the end of their growing season. Perennials are plants that live for more than 3 years. There are both woody and herbacious perennials. Woody perennials are plants that lose their leaves in the fall but their woody stems are persistent throughout the winter and they will leaf out each spring; herbacious perennials are those that die down to ground level with the first frost but in the spring the roots produce new growth. Peonies and Chrysanthemums are examples of herbacious perennials, azaleas are an example of a woody perennial.
Most plants should be tagged as annual or perennial, but if they are not you might be able to tell by the size of the plant. Those in small containers are almost always annuals; those in 1-gallon or larger containers are nearly always perennials. Perennials cost more than annuals but they last for years so I think it is money well spent. If you're looking through a catalog and can't tell whether the plant is annual or perennial, type the name of the plant into your web browser and you should come up with the right answer.
Best wishes with your garden!
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