Perennials are important elements in almost every landscape design. Unlike annuals that grow for only one season or biennials that grow for two seasons, perennials come back season after season.Trees and shrubs are, technically, woody perennials that slow their growth or go dormant each winter but their branches and trunks remain intact. The above ground parts of many herbaceous perennials, however, do die in the winter.One reason often given for planting perennials is that they need no maintenance. This isn’t necessarily true. They may need less maintenance than, say, annuals but they still need maintenance. For example, those herbaceous perennials that die back each winter have to be cut back to ground level and composted. Be sure not to disturb the roots. They continue to grow until the ground freezes.Some perennials don’t like confinement. They like to spread out, sometimes choking out adjacent plants. The remedy is to split them. Dig up the whole plant. Lay it on a tarp and split the roots into four sections. Replant one of the quarters in the hole from which it came. You can replant the others in planting beds on your property, give them to friends or donate them to a charitable plant sale. Splitting can be done now, in the month of June, but not in July or August. Perennials can also be split in the fall.Other perennial maintenance tasks aren’t that different from what you will encounter with other types of plants. These tasks include deadheading to encourage more flowers. Then there’s weeding, fertilizing, and watering if you don’t have enough rain. The result will be beauty and enjoyment for many years to come.