Firewise Landscaping with Succulents
Camille Newton’s succulent garden, which she enjoys tending as a respite from her busy medical practice, served as a firebreak during the 2017 Lilac Fire that destroyed neighboring homes in her north San Diego community of Bonsall. This photo of her garden is on page 51 of the second edition of Designing with Succulents ~
Soon after the wildfire, in a “Saved by Succulents” segment, Camille and I were on KFMB-TV News explaining how a landscape of moisture-rich plants can be firewise as well as waterwise. I also made a short “Succulents as Firebreak” video of Camille’s garden five days after the wildfire. Her story is both harrowing and remarkable. The video is a must-view whether you live in a fire-prone area or not. [Read more]
Ten years earlier, in Oct. 2007, the succulent garden on the cover of the first edition of Designing with Succulents also “saved” a Rancho Santa Fe home. Neighboring houses burned to the ground.
Go to my Top Six Firewise Succulents page
View my 6-minute video: Do Succulents Burn? In it I compare the combustibility of jade, aloe, aeonium, firesticks, elephant’s food and paddle cactus to branches cut from bamboo and oak trees.
Oct. 2007: Did Succulents Save Her Home?
SUCCULENTS have soared in popularity recently because they’re drought-tolerant, easy-care and just plain cool to look at, and now there’s another compelling reason to grow them: They’re fire-retardant. During last month’s wildfires, succulents — which by definition store water in plump leaves and stems — apparently stopped a blaze in its tracks.
“Succulents saved our home!” Suzy and Rob Schaefer wrote in a jubilant e-mail to friends and family after they returned to their fire-ravaged neighborhood in Rancho Santa Fe. The tabloidian statement is out of character for the low-key couple—he’s retired and she’s an artist—but it seems justified.
Their garden of aloes, agaves, euphorbias and more—created by Suzy with the help of San Diego landscape architect Robert Dean—encircles the Southwest-style home, which is adjacent to a palm- and eucalyptus-filled canyon. The garden is intact, but many of the canyon’s trees are blackened skeletons.
A tentacle of the Witch Creek fire, driven by high winds, roared down the canyon, which runs along the edge of the Schaefers’ back yard.
“Flames came within 6 feet of the house, then stopped,” Suzy says.
Shielding the most vulnerable corner of their home is an unassuming succulent that is common yet has no common name: Aloe arborescens. As it held off the flames, its fleshy leaves cooked and turned the color of putty.
Aloe arborescens, native to South Africa, grows throughout Southern California; dense plantings of it rim the cliffs of coastal communities. Its tapered green leaves are serrated on the edges, but not sharp, and radiate from a central stem, forming starfish-like rosettes. These overlap into mounding plants that grow 5 or 6 feet high, and as wide. In midwinter, the plants send up brilliant orange flower spikes that, ironically, often are described as torchlike.
Wildfires are opportunistic; they focus on easy fodder, in this case the canyon’s dry leaves and wispy fronds. Flames from the canyon lapped at the Schaefer garden, which sits just beyond the bank.
Seeking fuel, the fire climbed part way up a eucalyptus; scorched the slope; probed aloes, jade plants and a succulent ground cover; and then retreated. Instead it engulfed and rapidly devoured an older home across the street.
“Succulents may broil or bake, but they don’t burst into flames or spread them,” says Don Newcomer, owner of Serra Gardens, a succulent specialty nursery that operated in Malibu for 25 years and will soon relocate south to Fallbrook for business reasons. When a wildfire threatened the nursery a decade ago, succulents halted the flames, Newcomer says, saving both his business and his home.
Eddie Villavicencio, deputy fire marshal for the San Diego Fire-Rescue Department, affirms that succulents are fire-retardant, especially jade and cactus. An exception are “certain ice plants, which if not well-maintained can be flammable underneath.”
His department, which also monitors erosion control, cautions against planting trailing ground covers such as Hottentot fig (Carpobrotus edulis) atop steep slopes; its moisture-filled leaves are heavy and roots too shallow to hold the soil.
Gary Lyons, curator of the desert collection at the Huntington Botanical Gardens in San Marino, is outspoken about his desire to see succulents used as perimeter plantings for homes in areas.
“After the Altadena fire in 1993, I could see that agaves, aloes and opuntia had not burned, but rather had cooked,” Lyons recalls. “They can’t carry a fire. I wondered why there was no code requirement or law that requires developers and residents to use succulents in high fire areas. Why should taxpayers shoulder the firefighting costs of a hillside development’s incendiary landscape?”
Why, indeed. Homeowners adjacent to wild lands may not realize it, but the plants with which they routinely surround their dwellings are infamously flammable (among them, pines, junipers, bougainvillea, flax and grasses). Basically, anything woody and twiggy is a potential haystack, ready to be ignited by the tiniest ember — especially in autumn, especially during a record-setting drought.
California native plants are wonderfully resilient when it comes to wildfires, but it’s not because they don’t burn; some of the most common natives such as the aptly named greasewood (Adenostoma fasciculatum) are highly flammable. Fire is part of the chaparral’s natural cycle, enabling seeds to burst open and fresh green growth to take the place of old. This makes natives admirable—ingenious, even—but not, unless they’re fleshy, fire-retardant.
“There is some confusion about the terms ‘drought-tolerant,’ ‘native plants,’ and ‘fire-retardant plants,'” Lyons explains. “Fire-retardant plants vis-à-vis cactus and succulents stand apart from drought tolerant and natives. A native plant garden in the chaparral is like growing Roman candles. Drought tolerant may not be much better.”
“After any brush fire, you’ll see succulents that were not burned,” agrees Newcomer, who, like Lyons, would like to see homeowner associations and similar groups provide cuttings of Aloe arborescens to residents as a community service. “Aloes may not be native to Southern California, but they’re not invasive, either,” Newcomer says. “It’s not like they escape and invade creek beds.” He adds that Aloe arborescens offers the same health benefits of Aloe vera — these and other “medicinal aloes” contain a viscous gel that purportedly aids the healing of minor burns.
If it seems absurd to legislate the use of succulents as landscape plants, it likely won’t be necessary. They’re already catching on. According to Ron Vanderhoff, nursery manager of Roger’s Gardens in Corona del Mar — which does the largest volume of sales of any independently owned garden center in the western U.S., “our business in succulents has risen from $40,000 in retail sales four or five years ago to $400,000 a year, and it continues to grow. No other category of plants in our store has shown anything close to this increase. We now do 7% or 8% of our volume in succulents.”
The reason has to do with the plants’ “simplicity of maintenance,” Vanderhoff says. “People are spending less time in their gardens, and succulents are less fussy than annuals and perennials. They also have a lesser need for water and fertilizer, so they’re more ‘green.’ And they’re very sculptural and artistic. Succulents provide drama with their structure, leaves, colors . . . they’re very expressive plants.”
They’re also easy to start from cuttings, which is how Suzy Schaefer filled her garden.
“I whack them back and replant them,” she says, adding that her garden “is not just a way to cover dirt. It’s a living thing, and half the fun is to enjoy it aesthetically. I love the shapes of succulents, and the way they look ordinary and then send up a bloom that knocks your socks off. Growing succulents is like collecting art or sculpture — better, because when you have too many, you just give them away.”
And as for those aloes, it appears their melted leaves protected the plants themselves; the centers of the rosettes are still a vibrant green.
More Firewise Landscaping Tips:
Remove flammable vegetation and debris. Reduce potential kindling by getting rid of weeds, dead or dying plants, and anything dry and twiggy.
Avoid planting trees and shrubs that drop quantities of leaves, contain volatile oils or resins, and/or copiously shed bark. Notoriously flammable (and unfortunately quite common) trees include blue gum, eucalyptus, acacias, junipers and pines.
Be aware that some California native plants are pyrophytic. Literally “fire loving,” these highly flammable plants depend on seasonal wildfires for regeneration or seed germination. Common ones include greasewood (chamise), sumac (sugar bush), creosote bush and California sagebrush. (Note: Many California natives, including manzanita, coffeeberry, ceanothus and oaks, are not pyrophytic and actually are slow to burn.)
Make sure trees and shrubs within 100 feet of your home are well trimmed and full of moisture. If your house is on a hillside, the recommended distance is 200 feet.
The ideal firewise landscape consists of low-growing shrubs, ground covers and fleshy succulents. To help retain soil moisture and minimize erosion and weeds, cover bare ground with redwood mulch or gravel. Keep plants well watered, especially during fall’s desiccating Santa Ana winds. Avoid a fire ladder: fuel-rich plantings that enable fire to climb up to your home.
Surround your house with a 30-foot fire break. In addition to plants that have a high moisture content, include one or more of these landscape enhancements: hardscape, a rock garden, a dry streambed and/or a swimming pool. All make excellent fire breaks.
For more information, plus a list of low-fuel, firewise plants, download the California Department of Forestry and Fire Protection’s publication, “Fire Safe Landscaping.”
Note: Some CA fire districts mistakenly recommend growing native plants to the exclusion of all others. Natives do regenerate beautifully after a wildfire but are no help slowing one down, in fact, many natives—such as creosote plant—are highly combustible. Another misconception is that it is more “green” to plant natives exclusively. This is based on the assumption that if a plant is not native, it must be invasive. Except for Carpobrotus edulis (an ice plant known as pickleweed or Hottentot fig, common to coastal areas), succulents are not invasive, and therefore pose no threat to the local ecology.
From Tom Karwin’s On Gardening: Resolve to become fire safe column in the Santa Cruz Sentinel 12/21/17:
“Within a home landscape’s defensible space, using fire-resistant plants adds to protection from fire. CalFire describes these characteristics of fire-resistant plants:
• Store water in leaves or stems.
• Produce very little dead or fine material.
• Possess extensive, deep root systems for controlling erosion.
• Maintain high moisture content with limited watering.
• Grow slowly and need little maintenance.
• Are low-growing in form.
• Contain low levels of volatile oils or resins.
• Have an open, loose branching habit with a low volume of total vegetation.”