Origin
The Lupinus argenteus Pursh ssp. rubricaulis (Greene) Hess & D. Dunn, commonly known as Redstem lupine, is a wild flowering plant species that belongs to the family of Fabaceae. The plant is native to North America, specifically in the western states, including California, Montana, Nevada, Oregon, and Washington.
Common Names
Aside from Redstem lupine, this plant has various other common names, including Silky lupine, Pink lupine, and Velvet lupine. Its name is derived from the Latin term "lupus," which means wolf, because some people believe that the plant devours the soil in which it grows, depleting vital nutrients for other plants, similar to the way wolves in a pack consume everything in their path.
Uses
Historically, it has been used by indigenous tribes for various purposes, such as food, medicine, and dye. The plant's seeds have been utilized as a food source, either raw or cooked. The Navajo tribes boiled the plant's roots and consumed them as a vegetable. The plant's flowers and leaves have also been used to make red and yellow dyes. Nowadays, Redstem lupine is grown as an ornamental plant species.
General Appearance
Redstem lupine is a perennial herbaceous plant that grows up to 40 inches tall. The plant has a woody red stem that is covered in fine silky hairs. The plant's leaves are pentafoliate and have a gray-green color on top, with a silvery underside. The flowers are pink, purple, or blue, and grow in a spiky raceme. The plant seeds are in a short, curved pod, and when they mature, they become hard and glossy.
Light Requirements
Lupinus argenteus Pursh ssp. rubricaulis requires full sunlight or partial shade for optimal growth. In areas with hot summers, it may require some shade during the hottest part of the day to prevent sun scorch. Without adequate light, the plant may become leggy and weak, and it may not produce as many blooms.
Temperature Requirements
This plant species is adaptable and can tolerate a wide range of temperatures. However, it prefers cooler temperatures and is commonly found in montane meadows and open pine forests. It can handle temperatures as low as -23°C (-10°F) and as high as 35°C (95°F).
Soil Requirements
Lupinus argenteus Pursh ssp. rubricaulis prefers well-draining soils that are moist but not waterlogged. It can tolerate a range of soils types, including sandy, loamy, and clay soils, but it prefers soils that are rich in organic matter. The plant is adapted to soils with a pH of 5.0 to 7.0.
It is important to note that this plant species has a taproot and does not transplant well once established. Therefore, it is best to plant it in its permanent location from the beginning.
Cultivation
Lupinus argenteus Pursh ssp. rubricaulis (Greene) Hess & D. Dunn, commonly known as Redstem Lupine, is a hardy herbaceous plant that is native to North America. It prefers to grow in well-drained soils and requires full sun to partial shade to thrive. The plant can tolerate a wide range of soil pH levels but grows best in neutral to slightly acidic soils with a pH range of 6.0 to 7.5.
Redstem Lupine is propagated from seed, which can be sown in the fall or early spring. The seeds require light for germination, so they should not be covered with soil. Instead, they should be placed on the soil surface and gently pressed down. Once the seeds have sprouted, thin the seedlings to 6 to 12 inches apart to provide enough space for the plants to grow.
Watering Needs
Lupinus argenteus Pursh ssp. rubricaulis (Greene) Hess & D. Dunn requires moderate watering, and the frequency should be determined by the moisture retention of the soil. The plant should be watered deeply but infrequently instead of frequent shallow watering, as this can lead to root rot. During periods of extended drought, the plant should be watered more frequently to prevent it from drying out.
Fertilization
Redstem Lupine is a legume, and therefore, it is capable of fixing nitrogen from the atmosphere. However, the plant can benefit from fertilization with a balanced fertilizer in the early spring before new growth begins. The fertilizer should be applied at a rate of 1 to 2 pounds per 100 square feet. Additionally, the plant can benefit from topdressing with compost or aged manure in the fall to provide organic matter to the soil.
Pruning
Lupinus argenteus Pursh ssp. rubricaulis (Greene) Hess & D. Dunn does not require pruning unless there are dead or damaged branches. In this case, the damaged or dead parts should be removed to promote new growth. The plant can also benefit from deadheading, which is the removal of spent blooms, to promote more flowering.
Propagation of Lupinus argenteus Pursh ssp. rubricaulis
Lupinus argenteus Pursh ssp. rubricaulis, commonly known as Ruby lupine, is a beautiful and easy-to-grow plant that belongs to the family Fabaceae. It is native to North America and has attractive red flowers that bloom in late spring and early summer. The plant is a biennial or short-lived perennial that can be propagated through various methods:
Seed Propagation
The easiest and most common way to propagate Ruby lupine is through seeds. The seeds can be sown directly in the garden or started indoors 6-8 weeks before the last frost. To start indoors, sow the seeds in individual pots or seed trays filled with a well-draining potting mix. Sow the seeds at a depth of ¼ inch and keep the soil moist but not waterlogged. The ideal temperature for germination is 64-70°F. The seedlings will emerge within 14-21 days. Once they have developed their second set of leaves, they can be transplanted outdoors.
Division Propagation
Ruby lupine can also be propagated through division, but it is a bit trickier than seed propagation. The best time to divide the plant is in spring when new growth appears. Using a sharp, sterilized knife, carefully divide the root ball into several sections. Each section should have a healthy shoot and a good root system. Plant the divisions in a well-draining soil mix and water them thoroughly. Keep the soil moist until the new growth appears.
Cuttings Propagation
Ruby lupine can also be propagated through cuttings, but this method is not commonly used because it is difficult to get cuttings to root. To propagate through cuttings, take a stem cutting in late spring or early summer. The cutting should be about 4 inches long and have several leaves on it. Remove the leaves from the lower half of the stem and dip the cut end in rooting hormone. Plant the cutting in a pot filled with a soil mix and keep it moist but not waterlogged. The pot should be kept in a warm, humid place until the cutting starts to root. This may take several weeks to several months.
Disease and Pest Management for Lupinus argenteus Pursh ssp. rubricaulis
Lupinus argenteus Pursh ssp. rubricaulis is also commonly known as redstem lupine, and it is a beautiful native plant found widely in the western United States. The plant is prone to various diseases and pests, and it is essential to understand its management.
Common diseases that affect Lupinus argenteus Pursh ssp. rubricaulis
The plant is susceptible to various fungal diseases, including root rot and powdery mildew. Root rot is a disease that rots the plant's roots, leading to the plant's death, and it is caused by the fungus Phytophthora sp. Powdery mildew, on the other hand, causes a white powdery coating to appear on the plant's leaves and stems, which can affect the plant's ability to carry out photosynthesis.
Managing Lupinus argenteus Pursh ssp. rubricaulis diseases
One way to manage fungal diseases is to ensure proper drainage in the plant's location. This can be achieved by planting the plant in well-drained soil, avoiding watering the plant too much, and ensuring proper air circulation around the plant. For powdery mildew, application of fungicides containing potassium bicarbonate can help to control the spread of the disease. Planting resistant varieties of Lupinus argenteus Pursh ssp. rubricaulis can also help to prevent fungal diseases from occurring.
Common pests that affect Lupinus argenteus Pursh ssp. rubricaulis
The redstem lupine plant is susceptible to several pests, including aphids, weevils, and spider mites. Aphids are tiny insects that suck the plant's sap, leading to leaf distortion and stunted growth. Weevils, on the other hand, are beetles that feed on the plant's leaves, causing notches and holes on the leaves. Spider mites are small pests that feed on the plant's leaf sap, causing yellow or white spots on the leaves.
Managing Lupinus argenteus Pursh ssp. rubricaulis pests
To manage aphids, application of insecticidal soap or neem oil can help to control their spread. Weevils can be manually removed, or the application of insecticides such as pyrethroids can be used. Spider mites can be managed by spraying the plant with water or insecticidal soap. It is also essential to ensure proper sanitation practices, such as cleaning up plant debris and removing damaged plant parts, to reduce pest populations.
Overall, managing the diseases and pests that affect Lupinus argenteus Pursh ssp. rubricaulis entails maintaining proper plant care practices, selecting resistant plant varieties, and utilizing appropriate pest and disease control measures. By doing this, gardners can ensure a healthy and beautiful plant that will thrive for years to come.
