What is the difference between an annual, biennial and a perennial?
Annuals are plants that live for only a year. Some annuals such as most poppy varieties will re-seed giving the appearance of a perennial. A biennial will die in its second year after germination but some varieties do re-seed and hence behave like perennials. They may flower in both the first and second years, or in the second year only. Perennials are plants that live for three or more years.