perennials
Perennials are non-woody plants that live longer than two years. They generally bloom once a year, for anywhere from a day to more than a month. Most perennials die back to their roots in the fall, although some varieties will remain green through out the winter. Some perennials, like hollyhock and delphinium have a short lifespan, and may live for only four or five years. Other perennial plants, such as, aster and peony, can last for decades with little attention. Perennial plants give you a large selection of colour options and you can look forward to their return every year. They are also considerably easier to move than most shrubs. Do not expect your perennial plants to flower the first year that they are planted. It will usually take the plant a full season to become well established and it will flower the second year.
Dividing Perennials
If the flower quality and quantity drops in your mature perennials this may be a sign of overcrowding, and they may need dividing. Some may simply have outgrown the place they are in or other plants, as they grow, may be creating too much shade for sun loving perennials. Many perennials form clumps of stems. These stems are actually individual plants with their own root systems. Some perennials cannot be divided, if they grow from one central stalk. Early blooming perennials should be divided in early fall. When all the leaves have fallen, gently dig up the plant and separate the roots of the individual clumps to be removed. Replant the removed plants in an appropriate place in the garden. Later flowering perennials should be divided in the same way in the spring, as soon as they are showing growth.
Perennial Maintenance
Routine feeding and watering will generally be enough to satisfy the nutritional needs of perennial plants through their growing season. Spent flowers on perennial plants should be removed, or deadheaded, to encourage flower production. Perennials may be pruned back and mulched for extra protection in the fall. This mulch should be removed in the spring. If you do not wish to mulch, leave foliage on plants, as leaves will collect snow for insulation and moisture during the winter. Dead foliage should be pruned away in the spring.