Plant Descriptions

Perennials--those non-woody plants that come back year after year--offer almost endless variety in color, texture, shape, and size, making them suitable for virtually any garden location. Many are prized for their flowers; aster and phlox are just two of these. Others, such as ferns and hostas, are valued for their foliage.

Unlike shrubs and trees, perennials do not have permanent woody parts. But while some die down completely at the end of each growing season, then reappear at the start of the next, others spend the winter as low tufts of foliage, ready to grow when weather warms. A third type is truly evergreen, with foliage nearly unchanged throughout winter.

All perennials have a minimum lifespan of more than 2 years -- but beyond this, longevity varies enormously. Some grace the garden for only a few years, while others survive much, much longer (peonies, for example, can live for generations).

Though flowering perennials are often grown in borders, you'll also find them just about everywhere else. They may replace the front lawn or fill a parking strip; they may be used in the vegetable garden to add color and edge planting beds. Some gardeners set them among established shrubs to provide variety and add a touch of color to a predominantly green, leafy planting.

Annuals - Botanically speaking, annual plants complete their life cycle in one year:

You place the seeds of last year's annual plants in the ground in spring
New annual plants sprout from the seeds
With proper care, during the course of the summer, these annual plants produce flowers
Toward the end of the growing season, their flowers yield seeds -- signaling to the annual plants that their life cycle is complete

Evergreens - The term, "evergreen" means having foliage that persists and retains its color throughout the year, rather than changing color according to the seasons. The term, "evergreen" is something of a misnomer, as the color in question needn't be green. For instance, Colorado blue spruce trees are evergreens, but the color they retain throughout the year is a silvery blue.

Shrubs - In arboricultural terminology, shrubs are low woody plants, usually with multiple shoots or stems from the base (height of 15 feet or less). A planting of shrubs is called "shrubbery."

Ornamental Grasses - What makes ornamental grass "ornamental?" Ornamental grass, unlike the grass we mow regularly, is not meant to be mowed, is not meant to be uniform, is not meant to be tread upon. The only purpose of ornamental grass is to be pretty, to be an "ornament."
Ornamental grass is used in landscape design the way one uses flowers, shrubs, and trees. In fact, it is often mixed with such plants to fill planting beds, creating diversity in terms of form and texture. When composing such planting beds, it is best to layer the plants, placing the tallest in the back, the shortest in the front and the rest in the middle.

Ground Covers - Groundcovers are low-lying plants, usually chosen with aesthetic considerations in mind and requiring minimal maintenance. If groundcovers are projected to cover large expanses of ground on the landscape, the initial cost will be much greater than for sowing grass seed; but groundcovers may save you money in the long run, as expenses such as tune-ups for lawn mowers will be eliminated. "Groundcovers" and "cover crops" are different groups of plants, despite some overlap. Cover crops are sometimes used as "living mulches," in which function they serve a role not unlike groundcovers. But cover crops are often tilled into the soil not long after being planted, simply to supply the soil with amendments, whereas groundcovers may inhabit a stretch of land for many years. Groundcovers can be saviors for homeowners who are stuck with having to mow steep slopes (or who are simply unable to get grass to grow in such areas!) If you are plagued by such a hillside and it is in a sunny area, my article about juniper groundcovers may be the answer to your problems (see sidebar, "Juniper Groundcovers").

Information from: http://landscaping.about.com/ and http://www.perennialfarm.com

443.610.2613