Mother Nature plays rough: our readers learn about freeze damage - California garden damage caused by December 1990's record-low temperatures

Sunset, Nov, 1991

THIS HAS BEEN A discouraging year for gardeners," laments Mary Ann Crandall of Santa Rosa, California. "I didn't think Mother Nature could play so rough."

After last December's record cold temperatures damaged or killed many garden plants--already stressed by four years of drought in California--we asked Sunset readers to tell us about the damage in their own gardens. More than a hundred replied. They, along with nurserymen and horticulturists, helped us prepare this report.

What did we learn after the Big Freeze about the hardiness of popular new drought-tolerant plants? Which ones are now proven survivors in drought and freezing weather? And which freeze-damaged plants should you replaced? Here are some answers.

HOW HARDY ARE NEW

DROUGHT-TOLERANT

PLANTS?

Many plants widely grown just within the last decade or so were among the casualties of the freeze. Here are the six most reported by our readers. Keep in mind that factors other than temperature--such as the age and health of the plant and whether it gets watered before a freeze--can also affect how well it survives. Also, reported temperatures can differ from the actual air temperature around the plant depending on the thermometer's accuracy and its proximity to the plant.

Blue hibiscus (Alyogyne huegelii). With few exceptions, it didn't survive prolonged exposure to subfreezing temperatures. It died at 28[degrees] and 20[degrees] in the San Francisco Bay Area, and lost all foliage at 26[degrees] in San Juan Capistrano (where it finally put out weak new growth by June). A few plants managed to pull through unscathed, under trees in Thousand Oaks and near an east-facing wall in Downey (both, low 20s).

Kangaroo paw (Anigozanthos). Hybrids in pots or gallon cans were killed out-right. Given shelter (under trees, or under eaves against south-facing walls), established plants in the ground survived at 22[degrees] to 26[degrees].

Anisodontea. This one was killed at 8[degrees] in Sebastopol, and at 12[degrees] in pots in Auburn. But in Ojai (low of 12 [degrees]), of five established plants that died back, two had new growth by April and bloomed by July. And in San Bernardino, plants survived nine days below freezing (low of 22[degrees] for two nights); foliage wilted, but plants rebounded quickly. Generally, temperatures in the mid-20s didn't bother them.

Myoporum parvifolium. Prolonged periods of sub-freezing temperatures turned this ground cover to straw (although at two locations in coastal Southern California, it survived without damage at 26[degrees]). Many plants, given up for dead, eventually put out new growth. Writes Maureen Green of Santa Rosa (low of 17[degrees], "While mournfully cutting back blackened branches, I found to my surprise tiny buds of green on the crowns. I cut out the dead branches and covered the plants with redwood mulch; those buds became shoots. In all, I lost only 4 plants of 40."

Nerium oleander 'Petite Pink' and 'Petite Salmon'. Temperatures below freezing killed even established plants to the ground throughout California. In Vista (low of 26[degrees]), a few plants put out weak new shoots from their bases in spring; their owners chose to replace them with "something hardier."

Scaevola 'Mauve Clusters'. Temperatures in the 20s and high teens severely damaged this purple-flowering ground cover in most areas but didn't kill it. In Davis (low of 18 [degrees]), it "looked as though struck by lightning--all blackish and shriveled." But green shoots appeared under dead growth by midspring.

OLD FAVORITES: THE

TOUGHEST SURVIVORS

Below we list 25 drought-tolerant plants with interesting blooms or foliage (mostly evergreen in mild climates) unfazed by temperatures that lingered for days in the teens.

"The champions are our many native plants," writes Margaret Flesher of Modesto. Woolly blue curls, for example, not only kept its green leaves in temperatures as low as 19[degrees]; but also bloomed heavily three months later.