Groundcover plants serve a multitude of roles in the garden.  They can control erosion, act as a living mulch, provide an alternative to lawns and in some cases they are the perfect foil for shrubs or small bulbs to grow up through.  There are numerous types, like strawberries and a variety of herbs, which are also edible. These edible groundcovers perform double duty and are especially effective in small gardens where space is at a premium.

"With a groundcover you can extend your landscaping budget and space if you can also harvest, say berries, if you're using low bush blueberries as a groundcover. It would give nice seasonal color in the fall and would also provide you with a harvest of blueberries and you would not have to segregate your food plants in their own separate plots out of view," said Susan Littlefield, Horticulturist at the National Gardening Association.  

"You get two benefits instead of just one, and it is a way for people who don't have a whole lot of space to have a dedicated space for a food garden. If you're gardening in a small lot you don't have a lot of space, but you can grow these plants and get a harvest from them and use space that might traditionally be devoted to ornamental plants. If you live in a city or suburban neighborhood, most people want their yard to look landscaped. In a typical gardening arrangement people put vegetable gardens out back. If you don't have a lot of space you can still get the ornamental landscape value that you normally want in your front yard and be able to harvest a crop at the same time," said Littlefield.

In my garden (I am an avid gardener in Atlanta), I grow creeping thyme that only gets about 2 inches high but has a spread of about 12 to 18 inches. It offers a welcome contrast to a purple leaved shrub that it grows under and the low granite wall it creeps over.  Depending on your needs, there are many different selections of culinary thyme (a perennial) that also make effective groundcovers.  If you have a large area to cover consider adding a tapestry of different types of thyme. One that I like is Thymus ‘Doone Valley,’ an evergreen selection that is hardy to Zone 4 and has foliage with a strong lemon scent.   Growing to about 5 inches high and 18 inches wide, this colorful thyme has dark green leaves flecked with yellow and tiny pinkish-purple blooms that are 3 to 4 inches long.  Just make sure your thyme gets plenty of sun and a well-drained soil.  You can use fresh leaves or harvest and dry them for use later. 

Another culinary creeper that also likes full sun is the prostrate form of Rosemary called Rosmarinus officinalis ‘Prostratus.’ This fragrant favorite grows about 3ft. high and 4 to 8 ft wide.  Whether you use it on your roasted chicken or steep it and add some to perk up your lemonade, this versatile herb is a good choice for the kitchen and garden. In the garden it makes a happy companion for roses.  

Origanum vulgare ‘Aureum,’ Golden Oregano, adds welcome gold color to the garden and is tasty too.  Plant it in full sun in a well-drained soil.  This robust grower has tiny leaves and grows 1 to 3 feet tall and 6 to 12 inches wide.  Combine it with thyme for a colorful carpet. 

Fresh strawberries picked out of your own garden are hard to beat and they produce a dense mat of textured green foliage that will help keep weeds at bay.  For the best results, keep this perennial well fertilized.  If you live in a zone that gets frost in the winter make sure to apply a good layer of mulch to protect the roots, just like you have to insulate your pipes to avoid a call to your local plumber.  Alpine strawberries may be grown from seed and although the fruits are tiny, they are tasty and ornamental. 

For shady gardens, Sweet Woodruff, Galium odoratum, will spread out and cover a large area in no time.  A mat forming perennial, the tiny white spring flowers are popular for using in May wine, a punch made with white wine, orange and pineapple.  Despite its delicate appearance, this plant is tough and can be cut back with a rotary mower if it gets too aggressive.  Hardy from Zone 4 to 8, Sweet Woodruff grows 5 to 12 inches high.