Bitterroot, scientifically known as Lewisia rediviva, belongs to the Montiaceae family, formerly placed in Portulacaceae. It’s a perennial herb with the species name “rediviva” deriving from Latin, meaning “brought back to life,” alluding to its ability to revive after periods of dormancy or dryness.
Bitterroot has a significant historical background, especially among Native American tribes, where it was a crucial food and medicinal plant. It was first documented by Western science during the Lewis and Clark Expedition in 1806 when Meriwether Lewis collected samples in what is now Montana. The plant’s resilience and cultural importance led to it being named the state flower of Montana in 1895. Indigenous tribes like the Salish and Kootenai have long revered it for its sustenance and healing properties.
This plant is native to western North America, ranging from southern British Columbia in Canada, southward through Washington, Oregon, Idaho, Montana, Wyoming, Colorado, Utah, Nevada, and into northern California and Arizona. It thrives in dry, rocky, and well-drained soils, often found in sagebrush plains or at higher mountain elevations.
Bitterroot is a low-growing perennial with a taproot, emerging in late fall or early spring with succulent leaves that wither as the flowering begins. Flowers are showy, ranging from deep pink to white, with 4-9 sepals and numerous petals, appearing on short stems. The plant goes dormant during the summer, with flowers blooming in spring, providing a stark contrast to the often harsh landscapes where it grows.
As a perennial, Lewisia rediviva can live for several years, but specific to its growth cycle, it has a seasonal dormancy. Each year, new growth emerges from the same taproot, allowing the plant to survive in environments with extreme temperature and moisture fluctuations.
Bitterroot adapts to USDA Hardiness Zones 3 to 8, reflecting its capability to withstand cold winters and dry summers. This range corresponds to its natural distribution across various climatic conditions in the western states, where it can endure both the chill of high altitudes and the heat of desert-like conditions.
Bitterroot (Lewisia rediviva): Characteristics
- Perennial Growth: Bitterroot is a perennial herb, meaning it returns year after year from the same root system, with periods of dormancy particularly during the dry summer months.
- Succulent Leaves: In early spring or late fall, it develops succulent, lance-shaped leaves that are fleshy and somewhat glossy, growing in a basal rosette. These leaves disappear as the plant prepares to bloom.
- Flowering: The plant produces vibrant flowers, typically ranging from deep pink to white, with a center of numerous stamens. Each flower has 4-9 sepals that look like petals, and many true petals, creating a showy display.
- Taproot: Bitterroot has a thick, turnip-like taproot that is white and starchy, which serves as a storage organ for water and nutrients, allowing the plant to survive in arid conditions.
- Dormancy: After blooming, the above-ground parts of the plant dry up, and it enters a dormant phase to survive the hot, dry summer. This dormancy is critical for its survival in its native environment.
- Habitat: It thrives in well-drained, rocky, or gravelly soils, often found in sagebrush plains, grasslands, and at the base of mountains. Its preference for dry conditions makes it well-suited to its native, often arid environment.
- Size: The plant itself is relatively small, with the above-ground portion rarely exceeding 6 inches in height when in bloom, although the root can be quite substantial.
- Pollination: Bitterroot flowers attract various pollinators including bees and butterflies, which are drawn to the colorful blooms. The plant relies on these visitors for pollination since it has no self-pollinating mechanism.
- Resilience: Known for its ability to ‘come back to life’ after extreme conditions, Bitterroot can recover from dehydration or cold, which is why its species name, “rediviva,” means “brought back to life.”
- Cultural Significance: Beyond its biological characteristics, Bitterroot holds cultural importance for Native American tribes, particularly the Salish, who use it for food, medicine, and in ceremonies. The plant’s roots are harvested and prepared in various ways, showcasing its utility and significance in traditional life.
Bitterroot (Lewisia rediviva): Cultivation
Soil Type
Bitterroot requires well-drained, sandy or gravelly soil. The soil should be poor in nutrients to mimic its natural habitat, as too fertile a soil can lead to weak, less resilient growth.
Planting
Plant Bitterroot where it won’t be disturbed, as its taproot can be quite deep. Sow seeds directly in the fall or early winter, or plant dormant roots in late fall. Seeds need a period of cold stratification, so autumn planting is recommended.
Sun Exposure
This plant thrives in full sun to partial shade. In areas with intense summer heat, some afternoon shade can prevent scorching.
Watering
Water sparingly, as Bitterroot is adapted to dry conditions. Over-watering can lead to root rot. During its growth period in spring, water only when the soil is dry. Reduce watering once the plant goes dormant in summer.
Mulching
Use a light mulch of gravel or small stones to help maintain soil temperature and moisture around the root zone, but avoid organic mulches that retain too much moisture.
Propagation
Besides seeds, Bitterroot can be propagated through root cuttings taken in late fall or early spring. However, division of the taproot is not recommended as it can severely harm the plant.
Fertilization
Minimal fertilization is needed; too much can be detrimental. If you must fertilize, use a very dilute, low-nitrogen fertilizer in early spring to support new growth without promoting weak, leafy growth at the expense of flowering.
Dormancy
Respect the plant’s natural dormancy cycle. In summer, when the plant goes dormant, reduce or stop watering, and avoid disturbing the area where Bitterroot is growing.
Pest and Disease Management
Bitterroot is generally pest-resistant due to its harsh growing conditions. However, watch for root rot if over-watered. Also, slugs can be a problem in wetter conditions; use natural controls if necessary.
Winter Care
In colder zones or during particularly harsh winters, a layer of mulch (like gravel) can protect the plant from frost heave. However, Bitterroot is quite hardy to cold once established, so extensive protection is generally not needed.