Home & Garden Columns

Green Neighbors: Endangered in Its Home, Enthusiastic in Gardens: Malva Rosa

By Ron Sullivan
Tuesday April 08, 2008
Leaf and blossom of Lavatera assurgentifolia, malva rosa, island bush mallow.
Ron Sullivan
Leaf and blossom of Lavatera assurgentifolia, malva rosa, island bush mallow.

Joe and I spent the other afternoon moving dirt and reshaping the malva rosa by the garage, to allow some sun on the pile we were making. This isn’t the first time we’ve radically reshaped the thing, and it won’t be the last. Except for the fact that it’s so inherently bewildering, I’d call this plant the ideal first thing to learn pruning with: it’s woody but soft; it puts out lots and lots of branches to choose from, and it can take a severe pruning and recover.  

It’s also quite malleable in form. I’ve seen hedges of it—good as a background loose hedge, not so good sheared into wan-looking cubes—and big full self-directed airy mounds, and what could pass for trees. 

Maybe it’s not quite a regulation-sized tree, but Lavatera assurgentiflora, the malva rosa or island tree-mallow, comes close. One source says it can attain a height of fifteen feet, and ours is close to that. It’s usually considered a shrub, though, and a highly decorative one. 

The legendary California plantswoman Lester Rowntree was fond of it. In her Flowering Shrubs of California and Their Value to the Gardener, she called it “a valiant battler with the elements and a courageous bloomer. In spring it is gay with flowers….when most wild shrubs are overtaken by drought and relax into rest, there are usually a few blooms left on the mallow. It is only when the cold January winds thrash it about that L. assurgentiflora begins to look depressed...” 

Rowntree praised its bright green maple-ish leaves and two-inch-wide flowers: “rosy pink, a little paler toward the center, and striped with deep purple-carmine, suggesting in their detail an old flower picture.” Her only caveats were that the mallow needed pruning to help it keep its shape, and that it could be prolific: “As it will volunteer all over the place, you may expect to see a whole forest of little Mallows.” We haven’t had volunteers, but the thing would eat the yard if we let it.  

Like its neighbor the Catalina ironwood, the island mallow is a Channel Islands plant that made good. Those islands are as close as California comes to a Galapagos, an evolutionary funhouse full of ancient relicts and newly minted neoendemics. Most of the specialties are plants, but the islands are also inhabited by an oversized scrub-jay, a miniature gray fox, and-formerly-the oxymoronic pygmy mammoth. 

L. assurgentiflora has a northern subspecies native to Anacapa and San Miguel Islands and a southern subspecies native to Santa Catalina and San Clemente. It has had to contend with browsing by exotic ungulates, notably goats, and few survive in the wild. On Catalina, it’s down to two isolated rocks near the island’s isthmus. Old accounts talk about forests of malva rosa on San Clemente, but the goats have pretty much done for them. 

But the mallow does well in cultivation, and has naturalized itself on the southern California mainland coast as well as parts of Baja California, Peru, Ecuador, and Chile. Several cultivars are available, one of which, Purisima mallow, is a hybrid between L. assurgentiflora and L. venosa from the San Benito Islands off the Pacific coast of Baja. 

The island tree-mallow’s closest relatives are all Mexican island species, with two occurring on goat-bombed Guadalupe Island. The other Lavateras are native to the Mediterranean region, central and eastern Asia, and Australia; a few are also tree-sized. The genus was named for the Lavater brothers, a pair of 16th-century Swiss naturalists. Lavatera is a member of the Malvaceae, the mallow family, along with hollyhocks, hibiscus, okra, cotton, and (in the latest classification) the cacao tree.  

You’ll see other bush-sized native mallows in the trade, including the endangered San Clemente Island bush mallow (Malacothamnus clementinus). They tend to be more compact than the tree-mallow and to have white or gray foliage, due to tiny hairs that may cause skin rash in the susceptible. They also bear their flowers in spikes rather than singly, as Lavatera does. 

Like Rowntree, contemporary garden writers stress the need for discipline. Carol Bornstein, David Fross, and Bart O’Brien, in California Native Plants for the Garden, refer rather harshly to the mallow’s “rank growth and coarse appearance [which] make it a poor choice for formal garden settings.” They also describe it as short-lived, vulnerable to a virus specific to the mallow family, and popular with leaf-eating insects, gophers, and deer. We’ve never has an insect problem on ours (knock wood) and we don’t have many deer or gophers in the neighborhood.  

On the other side of the ledger, it grows fast and tolerates wind and salt spray. No salt spray here either, so the fast growth is untrammeled except by the garage and people getting there. And periodic attacks of Felco shears and Silky saws, of course.  




Ron Sullivan is a former professional gardener and arborist. Her “Green Neighbors” column appears every other Tuesday in the Berkeley Daily Planet, alternating with Joe Eaton’s “Wild Neighbors” column. Her “Garden Variety” column appears every Friday in the Planet’s East Bay Home & Real Estate section.