Overview
Lupinus pusillus Pursh var. intermontanus (Heller) C.P. Sm. is a small flowering herbaceous plant in the legume family, Fabaceae. It is native to western North America, particularly in the intermountain regions of the United States and Canada. This plant is often referred to as the “dwarf lupine.” With its colorful appearance and numerous benefits, this plant is often grown for ornamental and medicinal purposes.
General Appearance
Lupinus pusillus var. intermontanus is a short-lived herbaceous plant that grows up to 20 cm tall. It has a slender stem with five to ten palmately arranged leaves that are green and glossy. Its leaves have leaflets that are narrow and oblong-elliptic, making them resemble fingers. This plant produces complex, showy, and attractive flowers that grow in clusters on terminal spikes. The flowers vary in color and may be lavender, blue, pink, or white.
Common Name
Lupinus pusillus Pursh var. intermontanus is commonly known as the dwarf lupine or the intermontane lupine.
Uses
Lupinus pusillus Pursh var. intermontanus has several uses in the ornamental and medicinal industries. As an ornamental plant, it brightens up gardens thanks to its colorful and attractive flowers. It is often used as a border plant or as an accent plant in rock gardens. As a medicinal plant, the plant contains alkaloids that have shown beneficial effects, including antitumor and antioxidant effects. Additionally, indigenous peoples in North America have used this plant for food. They roast and grind the seeds of the plant into flour, which they use as a food source.
Light Requirements
Lupinus pusillus Pursh var. intermontanus (Heller) C.P. Sm. typically requires full sunlight to grow properly. The plant cannot tolerate shade or partial shade. Therefore, it is ideal to grow this plant in areas that receive direct sunlight for at least six hours per day.
Temperature Requirements
This plant thrives in a wide range of temperatures, from frost-prone areas to semi-arid regions. However, it performs best in temperatures that range from 10°C to 30°C. The plant can tolerate low temperatures, but it cannot survive in temperatures that fall below -30°C. Therefore, the plant is recommended for hardiness zones 3 to 8.
Soil Requirements
Lupinus pusillus Pursh var. intermontanus (Heller) C.P. Sm. prefers well-draining, sandy, or loamy soils. The plant requires soils that are slightly acidic, with a pH range of 5 to 7.5. It does not tolerate wet soils or those that are too alkaline. Therefore, it is best to plant the species in areas that do not experience waterlogging or flooding. The plant also requires moderate amounts of nutrients, especially nitrogen, to grow and thrive.
Cultivation Methods
Lupinus pusillus Pursh var. intermontanus (Heller) C.P. Sm. thrives well in well-draining soils that are rich in organic matter. The plant grows best in areas with full sunlight exposure but can also tolerate partial shade. You can cultivate this plant using seeds or transplants.
When starting the plant from seeds, plant them 1 to 2 inches deep in a pot and ensure the soil is moist. Ensure to keep the soil moist but not waterlogged throughout the germination period. Once the plants reach a height of three inches, transplant them to their permanent location. For transplanting, ensure you have spaced the hole about 1-2 feet apart.
Watering Needs
Lupinus pusillus Pursh var. intermontanus (Heller) C.P. Sm. requires frequent watering, especially during the growing season. For the first few months, ensure you keep the soil moist but not waterlogged until the roots establish. Once the plants have established, you can reduce watering to once a week. During the dry months, you can increase watering to two to three times per week, depending on the soil moisture content, to prevent the plant from drying up.
Fertilization
Lupinus pusillus Pursh var. intermontanus (Heller) C.P. Sm. requires regular fertilization to promote growth and development. You can apply a balanced fertilizer with a ratio of 10-10-10 every two months. Fertilize the plant early in the growing season, then when it is at its peak growth stage, and once more at the end stages of the growing period.
Pruning
Pruning Lupinus pusillus Pursh var. intermontanus (Heller) C.P. Sm. is necessary to promote the growth of new shoots and leaves. After the plant has produced flowers and the blooms have faded, use sterilized shears to clip off the spent blooms. You can also prune the plant's excess branches to improve airflow and sunlight penetration. Pruning helps minimize pests and diseases, thus keeping the plant healthy and robust.
Propagation of Lupinus pusillus Pursh var. intermontanus
Lupinus pusillus Pursh var. intermontanus is a herbaceous plant native to western North America. Propagation of this plant is relatively easy, and it can be propagated by seed, cuttings or division.
Seed propagation
Seed propagation is the most common method of propagating Lupinus pusillus Pursh var. intermontanus. The plant produces seeds in the late summer or early fall, which can be collected and sown directly into the soil, or stored for later use. The seeds should be sown at a depth of around 1/4 inch and kept moist until germination, which usually occurs within 2-3 weeks.
Cutting propagation
Cuttings can be taken from Lupinus pusillus Pursh var. intermontanus in the early summer. Cuttings should be taken from the tips of the plant, and should be around 3-4 inches long. The cuttings should be planted in a well-draining potting mix, and kept moist until roots develop, which usually takes around 4-6 weeks.
Division
Division can be used to propagate Lupinus pusillus Pursh var. intermontanus and is best done in the spring or early fall. The plant should be dug up and gently separated into smaller plants. The smaller plants can then be replanted in a well-draining soil mix and kept moist until established.
Disease and Pest Management for Lupinus pusillus Pursh var. intermontanus
Lupinus pusillus Pursh var. intermontanus, commonly known as Intermountain lupine, is a beautiful wildflower that is native to North America. This plant is generally hardy and resistant to most pests and diseases. However, in some conditions, it may still fall prey to certain diseases and pests. Therefore, it's crucial to implement proper disease and pest management practices to keep the plant healthy. Here are some common diseases and pests that might affect Intermountain lupine along with their management techniques.
Diseases
Anthracnose: Anthracnose is a fungal disease that can affect various parts of the lupine plant, including the leaves, stems, flowers, and seeds. Symptoms include dark spots on leaves, stem cankers, wilted flowers, and seed discoloration. To manage anthracnose, remove the infected plant material and dispose of it properly. Avoid overhead watering and improve air circulation around the plant to prevent the disease from spreading. Fungicidal sprays may also be used in severe cases.
Root rot: Root rot is a fungal disease that can cause the plant's roots to decay. Symptoms include wilting, yellowing of leaves, stunted growth, and plant death. To manage root rot, avoid over-watering and ensure proper drainage. Remove infected plant material and replant in a new area. Fungicide may also be used in severe cases.
Pests
Aphids: Aphids are common insect pests that can weaken the plant and stunt its growth. Symptoms include distorted leaves and honeydew on the leaves. To manage aphids, spray the plant with a strong jet of water to wash off the insects. Alternatively, use insecticidal soap or neem oil to kill the pests.
Bean leaf beetle: Bean leaf beetles are small insects that can cause significant damage to the lupine plant. Symptoms include skeletonized leaves, browning of leaves, and plant death. To manage bean leaf beetles, handpick the insects and dispose of them. Alternatively, apply insecticidal sprays to the plants.
Spider mites: Spider mites are tiny arachnids that can suck the sap from the lupine plant, causing it to weaken and die. Symptoms include yellowing leaves and fine webbing on the plant. To manage spider mites, spray the plant with a strong jet of water to wash off the mites. Alternatively, use insecticidal soap or neem oil to kill the pests.
Implementing these disease and pest management techniques can help keep your Lupinus pusillus Pursh var. intermontanus healthy and thriving. In case of severe damage or infestation, consult a professional for appropriate management strategies.
