Origin and Common Names
Lewisia rediviva Pursh var. minor (Rydb.) Munz, commonly known as bitterroot, is a perennial plant species of the family Montiaceae. It is native to western North America, specifically found in the mountainous areas of California, Idaho, Montana, Oregon, Washington, and British Columbia.
Appearance
The plant typically grows up to a height of 3 to 6 inches and forms a rosette of hairy, thick, fleshy, and olive-green leaves that measures ¾ to 2 inches long. The leaves are spoon-shaped and have a thick midrib. Each plant produces a single stem that bears a single flower with a diameter of up to 2 inches.
The flowers of Lewisia rediviva open in the morning and close in the evening. They have five to seven petals that vary in shades from white, pink, to deep rose with a central cluster of yellow stamens. After flowering, the plant produces a slender, elongated capsule with several seeds that have a distinctive fan-shaped surface.
Uses
Bitterroot has edible roots that are used in traditional indigenous cuisine. The plant holds significant cultural and spiritual value in Native American communities where it was an essential medicine and spiritual plant. Today, it is a popular ornamental plant in gardens and parks, valued for its attractive, showy flowers and unique foliage.
In addition to its cultural and ornamental uses, bitterroot is an essential component of the western ecosystem. It is a pioneer plant that is the first to appear after a disturbance or fire event and helps in the re-establishment of native vegetation. It provides an essential source of nectar for pollinators, including bees and butterflies, and serves as food for several wildlife species, including deer and bighorn sheep.
Light Conditions
Lewisia rediviva Pursh var. minor (Rydb.) Munz is a sun-loving plant that requires full sun to partial shade. It grows best in areas that receive at least 6 hours of sunlight per day. However, in hotter regions, it can tolerate light shade to avoid dehydration and sun scorch.
Temperature Requirements
Lewisia rediviva Pursh var. minor (Rydb.) Munz grows well in climates that experience cold temperatures. The plant thrives in areas with temperatures ranging from 0°C to 25°C (32°F to 77°F) during the growing season. During winter, the plant can tolerate low temperatures that range between -20°C to -28°C (-4°F to -18.4°F).
Soil Conditions
Lewisia rediviva Pursh var. minor (Rydb.) Munz requires well-draining soils that are sandy or gravelly. The plant can tolerate slightly acidic to slightly alkaline soils. Soil pH levels ranging from 5.8 to 7.6 are ideal. It is important to note that the plant is susceptible to root rot if grown in poorly drained soil.
Cultivation Methods
Lewisias thrive in well-drained soil with a neutral to slightly acidic pH. You can grow them in rock gardens, alpine gardens, or even in containers. They prefer a sunny location but will also tolerate partial shade. Make sure to acclimate the plants before transplanting them to the garden. Space them approximately 6-8 inches apart to allow for proper air circulation.
Watering Needs
Lewisia rediviva Pursh var. minor (Rydb.) Munz plants require moderate watering during their growing season. Ensure that the soil is moistened consistently but never overly wet. Watering should be done early in the morning to avoid the risk of fungal diseases.
Fertilization
Lewisias are light feeders and do not require much fertilization. You can fertilize once per month with a balanced fertilizer when the plant is actively growing. Avoid fertilizing in winter when the plant is dormant.
Pruning
Deadheading spent flowers is essential to prevent seed formation and to promote flowering. You can prune the plant after the blooming season to control its size or shape. Ensure that you remove dead leaves and flowers regularly to promote good health and growth.
Propagation of Lewisia Rediviva Pursh var. Minor (Rydb.) Munz
Lewisias can be propagated by both vegetative and sexual means. Vegetative propagation is usually achieved through divisions, and sexual propagation is through seed germination.
Divisions
Divisions are an easy and quick way to propagate Lewisias, but they should only be done during the plant's dormancy period. This is typically in early spring or late fall. First, the plant is carefully lifted out of the ground. Then, the roots are gently teased apart and divided into smaller sections, each with a portion of the rhizomes.
Once they have been divided, the divisions should be planted in well-draining soil with partial shade for a few weeks until they start to establish new roots. After that, they can be transplanted into their permanent location in the garden.
Seed Germination
Lewisias can also be propagated through seed germination, but this method requires more time and patience. The seeds should be sown in a well-draining, sandy soil mix and kept moist until germination, which usually takes two to three weeks.
The seedlings should be kept in a protected area with filtered sunlight and good air circulation. The seedlings should be transplanted to their permanent location in the garden once they are large enough to handle and have developed a few sets of true leaves.
It is worth noting that Lewisia rediviva Pursh var. minor (Rydb.) Munz can self-sow readily in favorable conditions, so if you don't mind a bit of unpredictability, leaving some of the plants to go to seed is an option.
Disease and Pest Management for Lewisia rediviva Pursh var. minor (Rydb.) Munz
Lewisias are generally healthy plants with few disease and pest problems. However, they can be susceptible to certain diseases and pests under certain conditions. Regular monitoring and timely intervention can help prevent or control these problems.
Common Diseases
1. Powdery Mildew: Powdery mildew is a fungal disease that affects many plants, including Lewisias. It appears as a white, powdery coating on the leaves and stems, which can cause them to turn yellow and wither. Powdery mildew is more common in shaded, humid conditions.
Management: To manage powdery mildew, remove affected plant parts and dispose of them away from the garden. Improve air circulation and reduce humidity by spacing plants further apart, and watering early in the day to allow leaves to dry off. Neem oil or sulfur sprays can also be used as fungicides.
2. Root Rot: Root rot is a fungal disease that affects the roots and stems of Lewisias. It is caused by wet soil conditions which lead to fungal growth. Affected plants may show stunted growth, yellowing, and wilting.
Management: To manage root rot, improve drainage by adding organic matter to the soil. Make sure not to overwater the plants. Remove and dispose of affected plant parts, and disinfect gardening tools with bleach to prevent spread. Fungicides such as copper sprays can also be used.
Common Pests
1. Aphids: Aphids are small, soft-bodied insects that cluster on the leaves and stems of plants, sucking the sap and causing the leaves to become distorted and stunted.
Management: To manage aphids, use a strong jet of water to dislodge them from the plant. Introduce beneficial insects like ladybugs or lacewings to feed on the aphids. Insecticidal soap or neem oil can also be used to control the infestation.
2. Snails and Slugs: Snails and slugs are common garden pests that feed on the leaves of Lewisias, leaving large holes and unsightly damage.
Management: To manage snails and slugs, remove any debris or hiding places that may provide shelter. Place copper barriers around the plants or sprinkle diatomaceous earth around the base of the plant. Use iron phosphate-based baits as a last resort.
By monitoring your Lewisias regularly and taking timely action against potential disease and pest problems, you can keep your plants healthy and vibrant for years to come.
