Gardening : Good Time for Plantings That Cover Lots of Ground
One more autumn opportunity--especially following that seed-sprouting combination of rain and warm weather--is the planting, or replanting, of ground covers.
Eliminating weeds beforehand is the most important part of planting ground covers, in large or small areas, as anyone who has tried to get weeds out of a ground cover--ivy or ice plant, for instance--can attest.
Once weeds like Bermuda grass or oxalis have taken hold, it is next to impossible to get rid of them. Usually the only solution is to start over.
The landscape department at Roger’s Garden in Corona del Mar has a formula that they say will get rid of 95% of all weeds. It uses a systemic herbicide sold as Roundup or Kleenup, which, given warm weather and time, will kill weeds down to the very tips of the roots, because it is carried throughout the plant by the plant itself.
The trick is that the plant must be actively growing, and here is where the rain and warm weather have helped.
Spray and Wait
Most seeds that are going to germinate have, by now, and the summer weeds are still growing because the weather has stayed warm. Spray them now and then wait 10 days. Most should be dead.
But to be sure, Roger’s follows up by grubbing out the dead weeds, sprinkling fertilizer over the soil and then lightly cultivating it with a steel rake. Then they water as if they were trying to germinate a new lawn and 10 days later they spray again with Roundup or Kleenup to kill the second generation of weeds. Ten days after this spraying, they plant.
(The only exception to this formula might be in areas choked with Bermuda or devil grass, and this weed is perhaps best dealt with in warmer weather to make sure the many underground roots and rhizomes are dead.)
What do they plant? I asked Lew Whitney at Roger’s and several other nurserymen in various parts of town to give me their five favorite ground covers.
Lew’s list included two for big slopes, trailing rosemary and trailing myoporum. The rosemary is an old standby--long lived, deep-rooted, reasonably quick to grow. It does get a little woody with age and the woodiest of stems should be pruned out to encourage new growth. Nice blue flowers adorn it in winter, and of course it smells great. It is available in flats.
The myoporum is one named Pacifica and is not sold in flats but in gallon cans. However, one plant can cover 7 to 10 feet in just two years so you don’t need many (but make sure weeds don’t start to grow between in the meantime). It is extremely tough, even growing in the Phoenix area, and doesn’t seem to mound higher than a foot.
A Sturdy Ice Plant
Also on his list is Aptenia cordifolia , an ice plant that is tougher than most and green too. He says its only drawback is that like all ice plants, it tends to mound higher and higher and eventually needs to be mowed or redone.
All of these are quite drought-tolerant, so they won’t need much water after the first year of growing.
Lew reluctantly adds Hahn’s ivy or needlepoint ivy to the list, because in sun or shade they are still among the densest and toughest of ground covers, even though they are so commonplace.
For shady areas, Lew likes an herb called pennyroyal, Mentha pulegium , that is sold by the flat. It stays very low and very green and is fragrant as well.
John Bauman at another coastal nursery, the Palos Verdes Begonia Farm in Walteria, also had prostrate rosemary on his list but added Acacia redolens , another tough, drought-tolerant, wide-spreading (to 15 feet) ground cover that is only available in gallon cans.
They also liked snow-in-summer, Cerastium tomentosum , for smaller areas because of its gleaming gray color and Polygonum capitatum for its pink flowers and reddish foliage. Both are very low-growing and sold by the flat. And, rosea ice plant is on their list, one of the tougher ice plants and one that stays quite low.
At the far end of the San Fernando Valley, Barbara Brown of Sperling Nursery in Calabasas suggested prostrate rosemary, myoporum and a native ground cover, the dwarf coyote brush (Baccharis pilularis) called “Twin Peaks.” This one is very drought-resistant and comes in flats. A brief item in the November issue of Sunset magazine points out some problems with baccharis but also offers some suggestions on how to avoid them and, problems or no, baccharis is one of the more natural-looking and fire-retardant ground covers for our slopes.
For smaller, flatter areas, Brown suggested wild or ornamental strawberry, Fragaria chiloensis , also a native to the Pacific Coast. This one stays very low but should be mown every few years. The pretty little isotoma is another suggestion for similar-size areas.
Surprisingly, the list doesn’t vary much for areas that are much farther inland. Kathryn Sayles of Greenfields Nursery in Murrieta suggested aptenia, baccharis, rosea ice plant and rosemary, but also added verbena (a favorite in the desert as well) and gazanias.
Use a Variety
A good plan of attack would be to use several of these suggested ground covers in any given area, planting them in colonies, which will break the monotony of a single ground cover and bring a little insurance that should one not do too well, others are growing.
While you are getting an area ready for planting or replanting, you might want to take a look at these ground covers in person.
The Los Angeles State and County Arboretum has 28 different labeled ground covers planted in beds near the entrance, and other plantings scattered throughout the arboretum. South Coast Botanic Garden on the Palos Verdes Peninsula also has sample plantings, and so does Roger’s Gardens.
Sybil Connolly, author of “In an Irish Garden,” a book that gathers together some of the loveliest of gardens from this “mild and equable climate,” will give an illustrated lecture on Irish gardens and their design on Thursday at 7 p.m. at the Academy of Motion Picture Arts and Sciences Theater, 8949 Wilshire Blvd. Tickets for the lecture and a dinner afterward are $100 per person, but tickets for just the lecture are available for $50 at the door or by calling (213) 273-3838. This special event is part of the fund-raising efforts of the Friends of French Art, and the insights into garden design by Connolly, who is a gardener and successful fashion and home furnishings designer, should be inspiring to those attempting to fashion a garden.
