The genus clarkia is home to over 40 different classified species of flowering plants. The vast majority of these are native to western North America, and they can be found growing wild along coastlands and in open plains.
Clarkia plants are part of the onagraceae botanical family, otherwise known as the evening primrose family. Members of this family are known to have beautiful crepe-like flower petals, similar to that of a California poppy.
There is a chance that you’ve heard of clarkia plants under the name of godetia. There was once a separate genus called godetia, but it is no longer recognized as those genus members were absorbed by the clarkia genus.
The scientific name clarkia is in honor of an explorer named Captain William Clark who was the discoverer of clarkia plants along the Pacific coast of North America and brought them back to Europe.
The clarkia plant is wonderfully easy to care for and makes a unique and charming addition to any outdoor green space. In our Marvellous List of Flowering Plants we cover many other plant species who are just waiting to bring color to your property!
What does Clarkia Look Like?
Clarkia flowers are simple in shape. Each flower is comprised of 4 sepals and 4 petals that are slightly ovular in shape. Flowers blooms in the summer or fall, depending on the local climate.
A clarkia flower will be either double or semi double, and petals have a crepe-like texture that is kind of frilly. Depending on the clarkia species, flowers will be any color from white, red, or pink, and different varieties may be spotted or streaked with another color as well.
Clarkia leaves are simple in shape and very small – usually only reaching 1-10cm. Each leaf has a noticeable vein and they are a soft green color with a matte texture.
Clarkias tend to stand very erect in the form of long and spindly stems. These stems are very thin and sway charmingly in the breeze. They can grow to be almost 2 metres in height. Along the stems grow evenly arranged leaves and flowers are borne at the ends of the stems.
Clarkia plants are annuals, meaning that they will completely their entire life cycle within the year. In order to have another bloom season they will have to be planted again, but luckily, you’ll find out later that they are devilishly easy to grow!
What are Some Clarkia Species?
Chaparral Clarkia (Clarkia Affinis)
The chaparral clarkia plant is endemic to California, and gets its name because it grows on chaparral slopes (which is a shrub based planted community), by coastal ranges, and woodlands.
This variety has the common spindly growth pattern and narrow leaves but flowers with deeper red or pink petals. They sometimes will have purple or red speckling or streaks as well.
Elegant Clarkia (Clarkia Unguiculata)
The elegant clarkia is also sometimes referred to as the mountain garland. This variety is also endemic to California and lives in more woodland habitats (especially oak tree forests).
This variety has spindly hairless stems that can grow to be over a metre tall, and narrow leaves. Elegant clarkias bear flowers that have paddle-like petal shapes that are a deep reddish purple color.
Lassen Clarkia (Clarkia Lassenensis)
The lassen clarkia can only be found in certain states in the US, specifially California, Oregon, and Nevada. This wildflower can be found growing in mountain plateaus and along slopes.
The lassen clarkia has similar stems and leaves but flowers are more bowl shaped. They have 4 large petals that have a light lavender base color, deepening to red towards the centre.
Farewell to Spring Clarkia (Clarkia Amoena)
The farewell to spring (also sometimes known as the ruby chalice clarkia) variety has a larger growing range and can be found all over western North America – from British Columbia southward to the San Fransisco bay area. They prefer to grow near coastal hills.
This variety is similar in appearance to most others in stem height and leaf shape, though they bear flowers that are a very pale pink or pale purple color.
Where do Clarkia Plants Grow?
Clarkia is a native plant to western North America. There, they can be found growing most happily in arid climates and along coastlines. They also thrive inland in woodlands, serpentine grasslands, and open plains.
Based on all of their growing regions, it is observable that they can tolerate both dry and moist conditions, and high sun exposure and low sun exposure. They can exist in USDA growing zones 3 through 12.
How do you Grow a Clarkia Plant?
Clarkia plants are wonderfully easy to grow, but they’re unique in the way that they do not seem to transplant very well. They are just delighted to sprout from seed! For this reason, there is a chance that you may not see cell packs of clarkia seedlings. They simply don’t want to seed indoors!
The best way to grow your own plant is by direct seed sowing outdoors once the last threat of frost has passed completely. This can be done at different times of spring, depending on how warm your growing location is.
Pick a spot on your property that receives full sun, and has soil that is moist and well drained. Plant seeds a good 4-6 inches apart. This may sound quite close together, and it is!
This is because that clarkia stems grow to be so tall and so slender that they tend to be slightly weak and unstable. By planting them closely together the stems can support one another, and there’s less chance of them breaking.
Directly sow clarkia seeds two more times at 2 week intervals. This will help extend your blooming period! In colder climates they can bloom all the way through late spring into summer and into the fall, and in warmer climates they can sometimes bloom into the winter and early spring as well!
Ensure that the soil never goes dry when seedlings are in this stage of life. They are not a particularly drought tolerant plant, and soil should be moist but never wet.
What are the Growing Conditions of Clarkia Plants?
The clarkia plant prefers to live in soil that is rather cool, remains completely moist, but that is also well drained. It is best to avoid nitrogen rich soil as this can interfere with their blooming capabilities.
One very interesting thing about this plant is that they seem to thrive in a specific type of soil called serpentine soil. This is rare soil that is derived from weathered ultramafic rock and can mostly only be found in the Appalachian mountains and mountains of California.
When plants are young and not yet established, seedlings should be receiving a high amount of water (keep soil moist at all times). Once a plant is well established, it only needs moderate amounts of water.
Clarkias can tolerate both full sun and partial shade conditions, though they should never exist in full shade as this could prevent flowers from blooming.
The clarkia plant is cold hardy, though it is not tolerant to frost. It is very important that they are not introduced to the outdoors until temperatures reach a minimum of 55 to 70 degrees Fahrenheit.
At the end of the day, clarkia plants are remarkably easy to care for, and can help a novice gardener feel like an expert. Just remember that they like to exist in moist soil that is not wet, and that they are sensitive to frost.
How is Clarkia Used?
The clarkia flower is such a charming and lovely variety with a wonderfully long blooming season. This makes them a very popular ornamental plant.
They’re commonly used as a border plant, a container plant, for mass planting, or as a lovely addition to a cottage garden. They do not exist very happily indoors, unless flowers have been clipped and will be kept in a vase.
Otherwise, this annual wildflower can be found growing prosperously in the wild as well. Even if these are not the cultivated variety, a clarkia wildflower meadow makes for a marvellous naturally ornamental sight.
This plant also holds a very important role in its growing regions’ local ecosystem. They provide both nectar for pollinators, but also provide habitats for those pollinators in their tall and closely growing stems.
This is a valuable place of refuge for those small but important critters. There are some species, like the Clarkia bee, that relies only on the clarkia flower for its nectar. The small forest of stems provide shelter for many species of caterpillars and moths as well.