Plant of the Month (May) : Elegant Clarkia - Clarkia unguiculata

Mother Nature's Backyard with pink Elegant clarkia (Clarkia unguiculata)

May is often a delightful month.  Depending on rainfall and temperature, most of the early-flowering plants like California poppy, Baby blue-eyes, Purple clarkia and the lupines have completed their flowering.  Now the later-blooming wildflowers like Yarrow, Globe gilia and several of the Clarkias come into their own.  Despite a bit of rain, the heat and dry winds of the past month have taken a toll on our coastal spring wildflowers.  Fortunately, a few dependable Clarkia unguiculata still add their color to Mother Nature’s Backyard.

Elegant clarkia (also known as Mountain garland) is an annual wildflower that brightens California foothills and lowlands (below 5000 ft.). Finding it in the wild is always an unexpected treat! The species distribution ranges from Northern California into Baja California, Mexico;   locally it can be seen in the Santa Monica Mountains and on Santa Catalina Island. 

Like many of our annual wildflowers, Elegant clarkia grows in several different climatic zones including the coastal area, inland foothills and even some desert foothills.  Among the plant communities which include it are the Coastal Strand, Coastal Prairie, Valley Grassland, Oak Woodland and Chaparral.  It often grows on dry, open slopes but is also seen in the shade of trees and larger shrubs.  Its  ability to flower in partial shade makes Clarkia unguiculata particularly useful in the garden.

In form, Elegant clarkia is upright, many-branched and somewhat stiff-looking if planted in sun, slightly less so in shade.  Tip-pruning when the plants are small will increase branching, and some gardeners choose to do so.  The main stalk is often tinged with red or purple, particularly in a hot, dry spring.  The leaves are simple, lance-shaped to linear and sparsely spaced along the stems.  Both stems and leaves are hairless (glabrous).

Elegant clarkia is a mid- to late-spring bloomer in our area (coastal Southern California).  It may start flowering as early as the beginning of April or as late as June depending on temperature and rainfall.  Seeds may be serially planted, every two weeks, to extend the bloom season into summer.   If you’re willing to keep the seedlings watered, serial planting is a nice trick to provide brilliant color in the summer garden.

The flowers of Clarkia unguiculata are quite spectacular.  They range in color from white and pale pink through salmon orange, bright pink and magenta.  Local wild populations are either magenta-purple or white.   In local gardens, the color palette seems to change from year to year.  Whether this reflects differential drought tolerance – or differences in breeding success the year before – has yet to be determined for our area.   But the yearly variability is just one of the fascinating characteristics of this species;  you literally can’t predict the color scheme from year to year!

Like other Clarkias, the flowers of Elegant clarkia are in ‘parts of four’ reflecting their position in the family Onagraceae (Evening primrose or Willowherb family).  This family includes the popular native Evening primroses (Oenothera species), the fuschias, the Suncups (Camissonia species) and the Willowherbs (Epilobium species).   All of these are frequently used in local gardens.

Elegant clarkia (Clarkia unguiculata): flower buds and flower

Elegant clarkia’s flowers are large (to 1 inch) and solitary on short flowering stems that are most conspicuous before the buds open (above).  The four colorful petals have a unique diamond or spade-like shape with a narrow, claw-like base (see photo above).  In fact, the petals are so unique that the species name unguiculata describes them (it means ‘little red claw or nail’). Flowers have 8 stamens (four red-orange anthers; four white) and a fused stigma that’s usually longer than the anthers.   Flowers are pollinated by native bees but they also attract hummingbirds.

While the native form has four petals, plants from purchased seed sometimes exhibit double or even triple the usual number of flower parts (see above).  It’s unclear to us whether these ‘fancies’ represent hybrids with another Clarkia species or are due to genetic variability – even gene duplication – within the species.  Other Clarkias are known to form inter-species hybrids - as well as individuals with chromosomal duplications - so either explanation is possible.  We’ll have to await an answer to the mystery of the Elegant clarkia  ‘fancies’.

Elegant clarkia (Clarkia unguiculata): young seed capsules

The flowers open over the course of several weeks, beginning at the bottom of the stem and working upwards.  The period may be as short as several weeks to as long as 4-6 weeks with adequate moisture.  At end of season it’s not unusual to see ripe seed capsules and the final flowers on a single plant.   The seed pods (see above) are stout, grooved capsules that start green-red and are dry tan at maturity.  The sections of the dry mature pod open by curling back from the top, releasing hundreds of tiny seeds.   

Elegant Clarkia has been a garden favorite for hundreds of years.  Seeds were exported to England in the 1800’s and Elegant clarkia is still planted by European gardeners.  It is loved by California gardeners – and not just native plant gardeners – throughout the state.  Part of the popularity is due to the lovely flowers.  Unless one detests pink and purple, it’s difficult not to be captivated by them. 

 

Mixed wildflower planting: Madrona Marsh Nature Center, Torrance CA

 

Another reason is Clarkia unguiculata’s adaptability.  While local wild Clarkias grow in sandy, well-drained soils, this species does spectacularly in clays.  It has a wide pH tolerance (6.5-8.5) so can be grown in alkali soils.   It does well in full sun – but also flowers in the high shade of trees, on the east side of walls, etc.   It is particularly usefully for those challenging areas with a combination of full sun and shade; like Yarrow, it helps to bridge transitional zones with simplicity and grace.

Elegant clarkia seeds are best planted in late fall or early winter – right before a good rainstorm. In common with most annual wildflowers, Elegant clarkia needs good soil moisture during its growth period.  Seeds germinate after the winter rains commence and seedlings are vulnerable to dry soils.  Supplemental irrigation may be needed during prolonged winter dry spells.  Once plants begin to flower they are fairly drought tolerant. 

Like all wildflowers, plants need a dry period for proper seed development.  Start tapering off irrigation as seed pods begin to dry; then let the pods develop until they are dry and beginning to open.  You can either let plants reseed naturally or save seeds for next year.  The seeds are loved by birds, so we suggest you save some for next year’s planting.  Seed saving is simplicity itself.  Once the pods begin to open, uproot the plants and invert the whole plant into a large paper bag.  The pods will dry and open, releasing the seeds.   Store seeds in a paper envelop or glass jar in a cool place indoors.  That’s all there is to it!

 

Elegant clarkia (Clarkia unguiculata) adds color to the May garden:
'Garden of Dreams' Discovery Garden - CSU Dominguez Hills, Carson CA

 

Annual wildflowers like Elegant clarkia can be used in many ways in the garden.  While they are often combined with other native wildflowers, this is not the only possibility.  We heartily recommend Elegant clarkia as a filler plant in developing gardens.  The flowers add a spot of color and mask bare areas between the growing shrubs.   Just be sure to mulch lightly – or not at all – in the areas with wildflower seeds.  If you want to reserve areas for wildflowers, consider using a gravel mulch (see http://mother-natures-backyard.blogspot.com/2012/07/understanding-mulches_23.html        for more on mulches).

 

Elegant clarkia (Clarkia unguiculata) with Birdseye-gila (Gilia tricolor; purple-white flowers),
California buckwheat (Eriogonum fasciculatum; green foliage) and Catalina silverlace
 (Constancea nevinii; silver foliage) : Mother Nature's Backyard

We like combining Clarkias with Birds-eye and Globe gilias (see above).  The light-colored Birds-eye gilia often finishes blooming just as the other two are taking off.   Clarkia are excellent choices for the habitat garden, providing nectar and pollen (native bees & hummingbirds) and seeds for seed-eating birds like finches, sparrows and the like.   There’s nothing prettier than a container filled with Clarkias on a sunny or shady porch.   Consider them also for the vegetable garden.  They  attract pollinators and the seeds are edible, raw or parched.

Elegant clarkia makes a long-lasting cut flower and is often used in bouquets and floral arrangements.   It is wonderful massed – truly spectacular!    Don’t worry about thinning – the plants will do that themselves and massed plants will even out-compete the weeds.   If you let the plants re-seed they will naturalize where ever they find a compatible place.  They are easy to remove if inappropriate and you can even use both foliage and flowers for green and gold natural dyes.

We hope you’ve enjoyed the story and pictures – and will consider Elegant clarkia for your own garden.   It’s truly a California treasure!

 

For a gardening information sheet see: http://www.slideshare.net/cvadheim/gardening-sheet-clarkia-unguiculata

For more pictures of this plant see: http://www.slideshare.net/cvadheim/clarkia-unguiculata-web-show

 

 

 

We welcome your comments (below).  You can also send your questions to: mothernaturesbackyard10@gmail.com