California’s Bushmallows

Talk to me about plants, and you’ll find me referring to many types as “one of my favorites.”  After a while it may seem that I have so many favorites that the designation doesn’t mean much.  They’re all my favorites, those native plants of ours.

That said, some do stand out.  California’s bushmallows of the genus Malacothamnus are one of those groups.  There are around 40 taxa (species, subspecies and varieties) of bushmallow in California, all of which share certain characteristics that make them choice garden subjects.  Bushmallows grow as an expanding patch of upright branches covered densely with (generally) silver-green leaves.  The foliage contrasts nicely with dark-leaved shrubs with similar requirements, such as ceanothus.  The abundant spring flowers are carnation pink.  Even with little or no supplemental irrigation, bushmallows look good in every season.

Bushmallows are also great plants for supporting wildlife.  They are one of our more edible native plants, so they host many larval insects.  The abundant seed provides forage for birds over many months, which also can shelter in the thicket of upright branches.  After the native oaks, bushmallows are perhaps the best plants for supporting our local ecology.

Here are a few bushmallows to consider for fall planting…

Malacothamnus clementinus - San Clemente Island bushmallow

Malacothamnus clementinus, San Clemente Island bushmallow: San Clemente Island is the most southern of California’s Channel Islands. In this warm, dry climate several plant species have evolved which are found nowhere else, among them San Clemente Island chicory, Munzothamnus blairii, and San Clemente Island triteleia, Trileleia clementina. The removal of introduced goats from the island has allowed these species to thrive after many decades of scarce survival. San Clemente Island bushmallow has been found in just a few rocky dry canyons, where the goats were presumably excluded by the difficult terrain. In these lean settings the plant grows sparsely as a patch of upright stems with large silvery green leaves. The spring blossoms are largely white with a pink blush. Like many members of this genus, this bush mallow explodes with growth when placed in a fertile, mild site. The plant spreads in all directions via rhizomes and blooms very generously for several weeks. Temperatures in the low thirties and thirty inches of annual rainfall do not seem to bother this plant at all. San Clemente Island bush mallow has done quite well in average soil and full sun in Santa Clara County.

Malacothamnus fasciculatus (Santa Clara County) - Chaparral mallow

Malacothamnus fremontii, Fremont’s mallow, is one of my favorite members of one of my favorite plant families, the mallows. It grows in open, dry areas in the interior coastal mountains and lower Sierra foothills from Shasta County to San Bernardino County. Its growth form varies with the growing conditions. In chaparral it tends to grow in an open, fountain form. This form may be enjoyed locally in Henry Coe State Park. In more fertile settings it grows as a dense expanding thicket of round silver white leaves to about seven feet. This form is most easily seen in my front yard, where a Fremont’s mallow has grown into quite a thicket. The spring bloom forms a dense blanket of round carnation-pink flowers. The subsequent seed provides abundant forage for birds, so consider leaving these on the plant until early spring. Fremont’s mallow accepts a variety of growing conditions. It maintains an attractive appearance without supplemental irrigation, once established.

Malacothamnus densiflorus - Many-flowered mallow bush

Malacothamnus densiflorus, many-flowered bushmallow, is found in Orange and San Diego Counties. It grows in an open, rounded form with round, gray-green leaves. In the spring it displays quite a bouquet of pink flowers and will continue to flower intermittently through the summer with a little supplemental water. Unlike many mallows, the many-flowered mallow bush does not spread via rhizomes. Its appearance may be improved by pruning back old flower stocks, and perhaps a third of the plant diameter in winter. The many-flowered mallow bush has performed well in Sunset zones 15 and 16.

Malacothamnus palmeri 'Hanging Valley' - Santa Lucia bush mallow 'Hanging Valley'

Malacothamnus palmeri, Santa Lucia bushmallow ‘Hanging Valley’: This beautiful bushmallow is a rare find in the coastal mountains of Monterey and San Luis Obispo Counties. This selection was made in the Hanging Valley region along Arroyo Seco Road in the Ventana Wilderness. It grows as a dense thicket of upright branches and lobed olive-green leaves. The leaves are soft with fine hairs, but they don’t seem to irritate the skin. In spring, each branch displays clusters of dark pink flowers, perhaps the most attractive in the genus. Like other mallows, this bush “has it all” with respect to wildlife support. It does need room to expand, however, since it will spread readily via rhizomes when happy.

Malacothamnus fasciculatus 'Casitas' - 'Casitas' Chaparral mallow

Malacothamnus fasciculatus, ‘Casitas’ Chaparral mallow:The chaparral mallow occurs in two populations, one in the SF Bay Area, the other in the coastal mountains from Santa Barbara County into Baja, Mexico. Currently there are four recognized varieties, but this is a highly variable plant so the distinctions are likely to change. The ‘Casitas’ selection is the nuttallii variety which grows in the Transverse Ranges. As the name implies, this selection was taken near Lake Casitas. It grows as an expanding thicket of branched upright stems with mint green foliage. The leaves of ‘Casitas’ are relatively large and flat for the species. Against this backdrop, a profusion of carnation-pink blooms appears in the spring. Sporadic light blooms appear through the summer and fall. Abundant seed follows, adding yet another characteristic that makes this an excellent plant for promoting birds. The chaparral mallow spreads quite widely via rhizomes under favorable conditions. In a local garden the ‘Casitas’ selection has grown quite vibrantly to about 6 feet tall and is spreading in all directions. The rhizomes can be dug out easily and will not immediately come back once removed. Try this lovely mallow in a sunny site where it has room to spread.