Perennials, especially small flowering plants, grow and bloom over the spring and summer and then die back every autumn and winter, then return in the spring from their root-stock rather than seeding themselves as an annual plant does. Herbaceous perennials,die back each winter. Most perennial flowers are herbaceous.
Perennial classifications are based on hardiness. Hardy perennials will normally survive the winter with little or no protection. Tender or half-hardy perennials will survive a mild winter, but may not survive a severe winter without protection. In colder climates, tender perennials are oftain grown as annuals. I think it is important to choose your perennials wisely as they DO require care and maintance. Once a perennial finishes blooming it looks much better if the spent flowers are removed for a neater look in the garden and continuing flower production. If you leave a few flower heads go to seed near fall, the seeds drop and produce more plants in the spring. After a few years of being in the garden if your perennials are happy they will multiply and you will need to divide the plants. This is always a great way to share your plants as well as keeping the plants healthy.
When to Divide and Plant
Summer planting is very successful, so long as plants are not allowed to dry out. Watering is especially important if the weather is hot and dry. Transplanting or dividing perennials already established in your garden is not recommended during the summer, except for Bearded Iris and Oriental Poppies, which should be divided only in July or August. Fall planting is highly successful in most regions. Early-blooming varieties will put on a colorful display in spring if planted in the fall. Dividing or moving perennials in the fall is usually very successful.