For those who frequent botanic garden or California Native Plant Society plant sales, the mad grab of flowering specimens is memorable. Bush monkeyflowers, in the genus Mimulus, are an increasingly popular target of this shopping frenzy. With relatively little effort, their cheerful blossoms light up the garden with a rainbow of colors for months on end.

Bush monkeyflowers - so named for the resemblance of some species within the genus to a smiling monkey - are highly desirable and surprisingly versatile native shrubs and subshrubs. Justifiably popular for their exuberant display of 1 to 2-inch wide blossoms, they jazz up mixed borders, rock gardens, and containers, combining beautifully with a host of plants that thrive in California's mediterranean climate. For the strictly native garden, mix them with other spring and summer-blooming plants such as Ceanothus, Salvia, Dudleya, Encelia, or Penstemon. Alternatively, avoid the segregated approach and integrate them with exotic species that share similar cultural requirements. For example, try weaving them through Cistus, Rosmarinus, Lavandula, Phormium, or the compact forms of Pittosporum. Monkeyflowers can also be used to soften the bold textures of succulents, such as the larger aeoniums, aloes, and agaves. Some of the low-growing, decumbent bush monkeyflowers are effective spilling over retaining walls, too.

A quick survey of bush monkeyflowers in the wild illustrates their considerable diversity. Plants range in size from 1 to 4 feet tall and equally wide and can be upright, mounded, or sprawling. Pairs of opposite, resinous leaves (hence their other common name of sticky monkeyflower) line the rather brittle stems. It is the flowers, however, that draw our attention; superficially resembling azaleas, the trumpet-shaped flowers vary in color from creamy buff to pale or golden yellow, peachy orange to burnt sienna and even brick red. The corolla is strongly two-lipped and the 5 petals are often deeply notched or fringed, creating a frilly appearance. The throat displays a contrasting color or prominent nectar guide lines, both of which serve as visual aids for pollinators.

Speaking of pollinators, monkeyflowers exhibit rapid movement, a rarity in the plant world. Take a moment and lightly touch the flower's white, two-parted stigma, then see what happens. It quickly closes up, "assuming" that a bee or hummingbird had deposited pollen from another flower while gathering nectar. When the plant senses the absence of pollen, the stigma will reopen. The stigma will continue to open and close until pollen is finally deposited. This visual cue makes it easy for plant breeders to track their controlled crosses.

As with many other California native plants, bush monkeyflowers were first cultivated in British gardens. Plants of Mimulus aurantiacus were grown as far back as 1796 from seed collected in Monterey or San Francisco by botanist Archibald Menzies. The May 1838 issue of Curtis Botanical Magazine includes a glowing description of Mimulus puniceus, "A very elegant shrub, flourishing in its native soil nearly the whole year ... it cannot fail to prove a great ornament to our gardens." In 1944, "Diplacus for Gardens and Roadsides" was published in the Journal of the California Horticultural Society [the precursor to today's Pacific Horticulture]. Written by Maunsell Van Rensselaer, then director of the Santa Barbara Botanic Garden, this comprehensive article makes a compelling case for the outstanding horticultural value of these showy natives.

Howard McMinn is familiar to everyone who grows California native plants, thanks to one of the most popular manzanita cultivars that bears his name. Monkeyflower enthusiasts may also know him for his early breeding work with the genus. In the late 1940s, he hybridized several species [now all lumped within the species Mimulus aurantiacus] and eventually selected two cultivars. Over the years, a handful of plant breeders have continued to experiment with bush monkeyflowers, aiming for larger and more vibrantly colored blossoms, more floriferous plants, greater tolerance of out-of-season irrigation, less sticky foliage, and more compact plants. * Thanks to their efforts, interest among commercial nurseries has increased and bush monkeyflowers are now more widely available than ever.

Three breeders are primarily responsible for the current menu of monkeyflower cultivars. While curator at the UCLA Botanic Garden [now known as the Mildred E. Mathias Botanical Garden], David Verity conducted a 20-year breeding program with bush monkeyflowers. His work yielded scores of luscious hybrids, some of which exhibited colors not seen in nature, such as violet-red and pink. His goal of developing true breeding strains with large flowers was curtailed when the university needed his growing grounds for other purposes. Fortunately, David distributed cuttings and seeds to interested nurseries and botanic gardens before the plants were destroyed. Some of his hybrids were eventually named and are still available, such as the vivid red 'Valentine', the white-throated 'Ruby Silver', the durable orange cultivar fittingly just called 'Hybrid Orange' and the eponymous 'Verity White'.

Richard Persoff became interested in monkeyflowers over 40 years ago. "Mimulus bifidus sang to me when I first saw it." He set out to collect cuttings and seeds of monkeyflowers from around the state for his breeding program and has released many outstanding cultivars to date, including 'Jack', 'Jelly Bean White', 'Sam' and 'Trish'. While striving to develop plants that are vigorous and pest-resistant, Richard has also selected for non-sticky cultivars. These are much easier to handle during propagation, a trait that commercial nurseries can appreciate.

Over at Ball Ornamentals, breeder Scott Trees has come up with the Curious Monkeyflower Series. These cultivars released in 2010 are the result of wild-collected monkeyflowers crossed with commercial material. Scott was aiming for profuse displays of large, frilly flowers borne on compact plants - and he has clearly succeeded. His four Georgie selections - in red, yellow, tangerine, and white - are simply stunning. In 2013 Ball released a new round of Scott's hybrids in what is called the Burst Series. These plants were bred to have larger flowers - these flowers are nearly twice the size of other cultivated Monkeyflowers. We are growing a red, yellow and dark orange selections within this series.

Although most of the shrubby monkeyflowers sold today are hybridized cultivars, it is helpful to know where the species occur in the wild. A stroll through some of California's most widespread plant communities - coastal scrub, chaparral, oak woodland, mixed evergreen forest, or coniferous forest - will likely yield several sightings. Natural populations occupy a variety of habitats, from rocky, sundrenched slopes to the dappled shade beneath oaks and conifers. They are not fussy about soil type, growing naturally in shales, sandstones, decomposed granite, and alluvium, but good drainage is critical. Depending upon annual rainfall, the flowering season can last from late winter through mid-summer. The plants invariably shut down once available soil moisture is depleted, a sign of their adaptation to California's long dry season. In places where coastal fog adds significant moisture, plants may blossom sporadically year-round.

Gardeners who follow these natural clues will be rewarded with masses of monkeyflowers in spring and early summer. A bit of judicious spring watering accompanied by tip pruning will likely promote another flush of blooms, thereby extending the flowering season. Pinching also promotes strong, dense growth that is particularly desirable for supporting cultivars with large blossoms and flower-laden stalks. When flowering ends, stop watering and allow the plants to rest for the remainder of summer. Plants grown in this manner are capable of living for several years; indeed, some species have been known to persist in cultivation for 10 to 12 years. Alternatively, plants can be grown like bedding plants and given regular watering and fertilizing all summer long. They'll perform beautifully but eventually wither due to root-rotting pathogens that are favored by the combination of warmth and moisture in the soil.

If left untended during the dry season, bush monkeyflowers have a rather bedraggled appearance. Once the wood has hardened, prune off at least one-third to one-half of each stem, leaving a few inches of the current year's wood. This removes the brown seed capsules and purplish-brown leaves that cling to the stems and makes the plants more presentable until they resume growth in the fall. Your efforts will be rewarded by more compact and vigorous plants the following season.

For inquiring minds, a few final words about the taxonomy of these native beauties are in order. The genus Mimulus is very well represented in California; by some counts it ranks as the 6th largest genus in the state with roughly 60 species, most of which are annuals. Mimulus also occurs in other parts of western North America, India, Australia, New Zealand, South Africa, South America, and Madagascar. Until recently, botanists separated woody members into the genus Diplacus, which consisted of 8 species [aridus, aurantiacus, bifidus {= grandiflorus or leptanthus}, clevelandii, longiflorus, parviflorus, puniceus, and stellatus] and several varieties. Today, all but M. clevelandii and M. stellatus are now lumped under M. aurantiacus, although botanists have yet to completely resolve all this name-calling. And to confuse matters even further, the genus has been removed from the figwort family [Scrophulariaceae] and placed in the Phrymaceae. Of course, none of this detracts from our real concern: a monkeyflower by any other name is still as pretty!

*Other monkeyflower breeders include Donald Sexton at UC Davis Arboretum, Phil Van Soelen of California Flora Nursery, and Lee Lenz at Rancho Santa Ana Botanic Garden.