What is the difference between an annual and a perennial?
An annual expends its entire life cycle in one year: from seed to flowering to development of seed heads. Most annuals produce flowers and need to be dead-headed to continue flowering. If annuals appear to return the next year, it is probably because they have self-seeded. A perennial (a category that includes perennial grasses) returns every year; however, in order to thrive, it will need to be divided in the spring or fall every three to five years. Most perennials develop as clumps that double in size each year; you know they need to be divided when flower (or in grasses, seed head) production declines.
