A friend of mine used to complain about people coming to his nursery asking for ground covers. “Ground covers!” he’d snort, “All plants cover the ground!” I think about his retort every time I am asked for a ground cover recommendation. My response is always “tell me how you want to use it and I’ll tell you what to plant.”
It turns out that what people want are spreaders; plants that grow low and wide. The problem is, they think that a spreader is a replacement for a garden of mixed plants — tall, wide, medium, upright, short and so on.
In fact, a lot of people are afraid of mixing plants, especially when it comes to slopes. I encourage them to look at our native hillsides. Mother Nature doesn’t cover hillsides with low, spreading plants. She covers them with a mosaic of plants in all different sizes, including spreaders. And so should we.
So, as spring progresses and you are no doubt bitten by the gardening bug, here are some suggestions for spreading plants and how to use them.
First, spreaders are perfect to plant along the edge of a garden bed. Visually, they contain the larger plants behind them and frame each bed as a distinct element.
Spreaders are good in-between and beneath larger plants, where they can complement an overall garden scheme. That’s how Mother Nature plants them, and that’s how they look their best.
Fast-growing spreaders fill in the empty spaces between newly installed plants. Over time, the slower, larger plants will replace them, but while we wait, the spreaders are something nice to look at.
Spreaders cover the soil, leaving little space for weed seeds to take hold.
Spreaders help keep the soil cool and hold moisture in as well. In effect, they are living mulch.
Easy, low-water spreaders for San Diego
Dymondia margaretae is one of the lowest-growing plants. Its 2-inch-tall spreading carpet of deep green blades is backed in silver with slightly rolled edges. This South African native spreads quickly over large areas, in full sun. Water it to get it started, then cut back. It is tough as nails and takes traffic very well. The only person I know who killed Dymondia watered and fertilized it regularly.
Arctotis aucalis, South African daisy, has felty gray leaves that make 6- to 8-inch-tall patches, up to 4 feet wide. As the weather warms in spring and cools in fall, big, brightly colored daisylike flowers appear in shades of hot pink, sherbet orange, brick red or lemon yellow. My favorite is a pink/orange combination called ‘Pink Sugar.’
Othonna capensis gets its common name “little pickles” for its little, cylindrical, succulent leaves. This diminutive spreader is no more than 2 inches tall, but from spring to fall, it is covered in equally diminutive bright yellow flowers. It doesn’t take traffic, but it is very cute!
Ceanothus griseus horizontalis, creeping California lilac, is a woody native whose deep roots are well suited for holding in a steep slope. Plants grow no more than 2 or 3 feet tall but reach a width of 10 feet. Rounded leaves are slightly grooved and deep green. In spring, plants are covered in deep blue flowers. Plant with native toyon, oaks and other handsome woody plants.
Frankenia thymifolia, sea heath, is a little challenging to find but well worth the search. This short (about 6 inches) and wide (1 to 2 feet) native of northern African and Spain is sea spray tolerant. Its stubby, wiry branches are covered in soft, deep green needles that look almost like fur. In summer, tiny pink flowers appear. I visited a garden recently with a small “lawn” of Frankenia. I had to look twice to figure out what it was.
Oscularia deltoides, pink ice plant, is not what you think of as an ice plant. Its succulent “leaves” are three-dimensional pyramids (hence the species name “deltoides”) and icy blue-green, arranged along bright pink stems. The plants form 6-inch-tall by 3- or 4-foot-wide patches that, in spring, are covered in tiny, purple/rose flowers with yellow centers. Plant this Oscularia around the base of agaves and other larger plants. Or stick stems in and around the edge of a large pot, so they can cascade over the sides.
Garden expert, designer and author Nan Sterman specializes in low-water, sustainable, and edible landscapes. Her website is www.plantsoup.com