white iceplant (Delosperma alba)

If you live in the hills or canyons around Los Angeles, expect a fire every 20 to 30 years. Fires are not only inevitable, they are essential to the existence of our chaparral ecosystem.
Many chaparral plants are not long-lived. As they gradually weaken and produce less green growth each year, they become more and more combustible. By the same token, it takes the heat of an inferno to open their seeds, and the ash left after a burn provides nutrients for renewed growth.
In the wake of this month’s deadly Southland fires, debates have arisen over which plants offer the greatest fire resistance. Unfortunately, no plant can survive flames that leap a hundred feet into the air, such as those witnessed in Laguna and Malibu.
Bob Perry, noted horticulturist and landscape architect, has done comprehensive research on the flammability of plants used in California landscapes.
“Probably the best way to prevent a potential brush fire from reaching you – if you live in a canyon or on a hillside – is to eliminate all vegetation growing within a 200 to 300-foot radius of your house. To maintain an existing landscape at minimum risk to yourself, thin out shrubs and trees so they cannot act as a large source of fuel for an approaching fire.
“Another good idea is to plant ground covers and low-growing shrubs which, of course, have less fuel volume than taller plants,” he said
When the vegetation around your house is reduced, however, the problem of soil erosion arises, especially if you live in a hilly area. On sloping terrain, the roots of plants keep soil in place. When these plants are removed, and heavy rains follow, mudslides may occur.
Iceplants should receive top priority for revegetation and relandscaping of burned areas around Los Angeles. They certainly do not guarantee protection
from a raging fire, but they do offer some fire resistance because of their succulent, water-packed leaves. And their dense root systems definitely control erosion on slopes.
Iceplants are native to South Africa, a country with Mediterranean climate similar to our own. Iceplants create a well-draining, sandy soil. They also will grow in somewhat compacted or clay soils but produce yellow leaves under such conditions, the result of impeded uptake of minerals due to inadequate oxygen supply to the roots.
Iceplants flower in a rainbow of colors, including red, pink, lavender, purple, orange, yellow and white. When several colors are planted together, the effect is stunning.
Avoid “heavy weight” iceplants, such as carpobrotus (Hottentot fig) and purple rosea. These are species which, due to the size of their leaves or the rapidity of their growth, may actually contribute to erosion; following a good rain, when their leaves are extra full of water, their weight has been known to pull soil down from slopes.
Three slow-growing iceplants are commonly recommended: delosperma alba, a white trailing variety; lampranthus products, a purple bush type that blooms throughout the year; and drosanthemum floribundum, highly recommended for steep slopes, and producing sheets of pale pink flowers in the spring.
While flowers give iceplants their special allure, leaf color, texture and shape make other types of succulents also worth consideration for hillside landscapes.
If fires are predicted or already burning near your home, thoroughly soak your plants.
Plants full of water may provide some small margin of safety between you and the flames.
“Ultimately, though,” Perry said, “the correct choice of building materials is going to save your house, not the plants growing around it.”