Edited by Dayle Cheever.
Is there a ground cover that you recommend? Please include the conditions that apply (slope, level, or heavily trafficked area).
Charlotte Getz: My favorite ground cover is Dymondia. It is tough, can take foot traffic, and has tiny, yellow daisy-like flowers. It is only about three inches tall and a grey-green color and drought tolerant once established. It is a nice contrast to green shrubs, trees, etc.
Kathy Copley: These days, with the advent of subsurface drip irrigation, I’m finding it more difficult to get successful coverage from installers who do not follow pre-watering procedures, which are critical to the survival of flatted ground cover, since the dripline is buried 3-6” below the surface grade. I like the following shrubby ground covers (not new, but worthy) that are mat-like, which allows me to use them in a foreground or border layer with perennials, shrubs, and succulents.
Dymondia margaretae- Silver Carpet (Asteraceae) WUCOLS classification is LOW water use for our coastal region. This is a tough, versatile, low-water lawn substitute from South Africa and is a low-growing, mat-like, dense ground cover with deep succulent roots. It gets only one inch high or less and spreads. Dymondia can be watered with micro-spray on a low pressure drip system or by overhead spray. The coverage is excellent, takes seaside conditions, some foot traffic, keeps down weeds, and provides a great silvery understory to bold succulents or shrubs of any size, in a way that showcases the plants without swallowing them alive. It would be great in any low-water use garden to blend with like-hydrozone plants, low-water use plants like California natives, Australian, Mediterranean, or South African plants. This may be the best ground cover I’ve ever seen for planting between steppers because it hugs the ground between the stones or steppers and fills in solid, and stays that way. It is truly a utilitarian plant with many attributes. Flowering is not one of its gifts, since the yellow daisy-like blooms hide amongst the foliage. There are some plants that just don’t shine until you partner them with other plants. This ground cover dances well with many plants and even takes some partial sun. Available in container sizes or flats. Because it is available in flats, it is more affordable to use as a ground cover in larger landscapes and as a foreground to other, taller, spreading shrubby ground covers. It is a tough survivor in a time when perennial ground covers with fine, fibrous roots are finding it more difficult to survive our currents standards for irrigation. This plant doesn’t seem to be affected by the increased soil salinity due to recycled water. How it does with boron, which also accumulates in soil with recycled water use, is unknown to me at this time. I guess we’ll see. It prefers reasonably well-drained soil and may even take heavier soil, if not overwatered, due to its fleshy root systems. Gophers may be unfriendly to this plant.
Teucrium cossonii-Marjocan Teucrium (aka Teucrium cossonili majoricum, Teucrium majoricum) (Lamiaceae, Labiatae) WUCOLS classification is LOW for our coastal zone. The origin of this plant is the Balearic Islands (Mediterranean). This is a mat-like perennial that gets only 4-6” high and 1-1 2/3’ wide. The leaves are dense, gray and aromatic. It prefers a reasonably well-drained soil as it is native to rocky limestone soil. It does get a fragrant, lavender bloom in the spring, which is prolific. That’s the good news. The bad news is that bees love it, so this is not a good ground cover for areas where bare feet and flip flops are prevalent. I would not use this plant between steppers without fully considering who the users are. It is reported to take temperatures below freezing, but is best in full sun. This is a great foreground ground cover or rock garden plant. It is suitable for drip irrigation, subsurface drip irrigation or micro-sprays. There is a similar plant, a cultivar in the trade that is called Teucrium chamaedrys ‘Nanum’- Germander WOCOLS classification is LOW water use. It is 4-6” tall and can spread 2-3’. Randy Baldwin at San Marcos Growers says it’s great for knot gardens because it takes shearing well. The foliage is green, as opposed to the gray of the T. cossonii. It is reportedly hardy to 10 degrees. I would love to see more of these mat-like ground covers that have fleshy roots and can take a low-water regime.
Susi Torre-Bueno: I’m sure I won’t be the only member to recommend Dymondia margaretae as a fabulous ground cover and lawn substitute on both flat and sloped areas. It grows only about 1” high, needs minimal water, and is sort of like a hard sponge to walk on. Grows well in full sun to part shade, never needs mowing, and has occasional yellow flowers. Excellent for foot traffic, and you can even park cars on it. If it gets a lot of water, it spreads rapidly, so don’t overwater it. For low-water ground covers you can’t walk on, I like lantana for something very colorful (it comes in a rainbow of color choices from near-white through yellow and orange to red and violet). The succulent known as ghost plant (Graptopetalum paraguayense) is an excellent ground cover, especially nice cascading down a slope. It is pale gray-blue in deep shade, changing to yellowish in full sun. I think it is prettiest in part to full shade. Here is an excellent article and photos by Debra Lee Baldwin: http://gardeninggonewild. com/?p=22817.
Scott Sandel: Baccharis pilularis ‘Pigeon Point’ is a great hybrid native ground cover that grows fast for applications such as big slopes. Plant at 48” or so apart, keeping that first row back from the curb or paving by 2-3 feet. This one dies back in the center far less than ‘Twin Peaks’.
Sheila Busch: I am really pleased with Dymondia margaretae. It is drought tolerant and it grows in heavy clay soil and full, hot sun in Escondido. It grows between pavers and along the walkway. It takes foot traffic as well as our dog peeing on it!
Pat Venolia: Dichondra argentea ‘Silver Falls’ gets my vote for a great ground cover, although I wouldn’t put it in a pathway. It is beautiful in a border and trailing down a slope. Fast growing and mildly drought tolerant once established.
Susan Starr: I like low growing Grevilleas, like Grevillea lanigera ‘Coastal Gem’. It grows about one foot tall and is supposed to get four feet across, although in my yard (La Jolla) it rarely gets more than three feet wide. Takes sun or light shade and seems to bloom most of the year. Very drought tolerant. You can’t walk on it, of course. Another favorite is Geranium ‘Rozanne’. This is a true Geranium (not a pelargonium) with lovely purple-blue flowers. It also blooms for much of the year at the coast. It prefers a little more water than the Grevilleas but is still fairly drought tolerant. Some protection from hot afternoon sun will give the best results. It’s not all that big, but perfect for filling in small areas.
Karin Esser: Wire fern, aka creeping wire vine (Muehlenbeckia axillaris). It grows beautifully in an area of Solana Beach that’s partially shaded by a Japanese black pine (Pinus thunbergii) and intermixed with sasanquas (Camellia sasanqua). The fern has pretty, small round leaves on dark wiry stems and needs little water. I trim it back once a year. The stems are graceful additions to flower arrangements.
Joan Herskowitz: I have had good luck with Othonna capensis, known as Little Pickles, as a ground cover that spreads and produces a mat up to about two feet in diameter and a few inches high. I have it growing in a number of spots throughout my garden in the coastal area. It is a sedum with inch-long blue-green succulent leaves and yellow daisy-like flowers that are produced on the short stems most of the year. Mine grow well in full or partial sun and under a low water regime (with water once a week in summer and once every 2-3 weeks in winter). Whenever I see a bare spot, I plant a cutting and more often than not, it grows to start a new mat.
Sandra Knowles: I can’t say enough good things about saving the wood chips the tree trimmers usually haul away. Spread them around the paths in the garden and if you can, let them compost and use them in garden beds. Happy gardening in the new year! G