You see the word perennial on plant tags and on garden web sites, but what is a perennial? The meaning of perennial is living for a long time. That’s what perennial plants do. They grow back every year, season after season. You only plant them once, saving money on your garden budget. Someone once said that friends don’t let friends plant annuals. That’s harsh, but you have to love a plant that needs so little from you.
Unlike annuals, which die each winter and must be replanted each spring, perennials grow back from roots that go dormant in the soil in the winter. Perennials can live as long as 15 years, or in the case of peonies, a human lifetime. Others, like mums, are short-lived, lasting just three or four years.
Perennials tend to be slower growing than annuals. They generally bloom for a single season, summer, spring or fall. There are everblooming perennials that bloom longer, but perennials are less about flowers than they are longevity. Perennials don’t bloom as much as annuals because they don’t have the same pressure to reproduce. They will be around for years, so they put their energy into growing strong roots instead of growing lots of flowers that will produce lots of seeds.
Some of the most popular perennials are coneflowers, blanket flowers, hydrangeas, clematis, daylilies, hostas, Siberian iris, delphinium, Veronica, Russian sage, catmint, yarrow, peonies, liriope, baptisia, sedum, Oriental poppies and coreopsis.
Perennials are good choice for gardens because they’re low maintenance plants that tend to be hardy. They don’t need a lot of help from you to survive. Keep them weeded and mulched, deadhead spent flowers and cut them back in the winter and they’ll be back in the spring. Perennials give resilience and consistency to your garden, providing a backbone around which you can plant short-lived flowers.
How do you grow perennials? You can buy container-grown plants from a nursery and transplant them, or you can buy seeds and sow them directly into the ground.
One of the best things about perennials is they grow bigger and better each year. Once established, perennials reproduce by developing colonies of new plants with their own roots and leaves. Dig up the new plants and transplant them elsewhere in your garden if you want more, give them to friends if you don’t. Some perennials reproduce so quickly they’ll overrun a bed if you don’t dig them out. The process of pulling clumps of perennials apart to create new ones is called dividing. The best time to do this is spring or fall. Dividing perennials keeps them healthy, too, by not letting them crowd themselves out.
Perennials reward each year. Pick varieties that thrive in your climate and get growing.
SOURCE:http://www.diynetwork.com/how-to/outdoors/gardening/what-is-a-perennial