Groundcovers and more
Groundcovers are what their name implies--and more. They are plants which can, respectively, carpet bare earth, substitute for grass, bind sandy soils, check erosion on hillsides, underplant trees and shrubs, survive neglect, and live long with little maintenance. Some adapt to life in shady situations; others endure full sun and drought; many can live where nothing else will grow. In general, they are tough and durable, low-growing and rapid-spreading shrubs, or other perennial plants. However, annual flowers can be used to achieve immediate results that are attractive and practical.
What a boon these are to gardeners! But be warned that some of the most vigorous kinds, useful for difficult sites, can become rampant pests if they escape into the good soil of your garden. The very qualities that make them desirable are their worst faults! Bear in mind that they must be able to take care of themselves, and so immune to hardships, that they are practically weeds. It is wise to plant such potential menaces where they can expand indefinitely without causing trouble, or to contain them within impassable barriers such as cement sidewalks or driveways. If you plant them adjoining a cultivated flower bed, they will move in and take over, and you will fight them forever.
The best plants for groundcovers are those with evergreen leaves that look handsome both winter and summer. There is a wider selection of these here on the North Coast because of our mild climate than where winters have subzero temperatures.
Groundcovers must be rapid-spreading. Suitable vines are those whose stems develop roots wherever they touch soil. Ideal shrubs are those that extend and multiply by means of underground runners or suckers; some have branches that root when they arch over and touch earth.
On level areas, almost any plant can cover the ground attractively, even though it grows in clumps instead of spreading. But on slopes, roots or rooting stems must form a continuous network to bind the soil surface, and roots must go deep if they are to keep the ground from breaking loose during our heavy rains.