Defensive Gardening

Did Succulents Save Her Home?
From the Los Angeles Times, November 8, 2007
By Debra Lee Baldwin

(excerpt)

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."