Origin
Lupinus arcticus S. Wats. ssp. arcticus, commonly known as Arctic lupine, is a flowering plant that belongs to the family of Fabaceae and is native to western North America including Alaska, British Columbia, and the Yukon Territory.
Common Names
Arctic lupine is commonly known as Arctic lupine, Hare’s-foot lupine, or simply lupine. The plant got its name from the Latin word “lupus” which means wolf and was given because this plant has the ability to fix nitrogen in the soil, that is, make it richer for other plants to grow.
Uses
Arctic lupine is typically used in ecological restoration projects, mine reclamation, and erosion control purposes due to its ability to improve soil fertility by fixing nitrogen. Additionally, the plant is a prominent source of foraging for caribou and hares in the arctic regions.
General Appearance
The Arctic lupine is a biennial or perennial herb that grows up to 60 cm tall with a taproot and numerous branches. The foliage consists of pinnately compound leaves with 7-11 leaflets each. The leaves are up to 10 cm long and covered with white hairs. The flowers have a blue to purple color and grow in a terminal spike or raceme. The fruits are pods that contain several seeds and can be from 4-9 cm long.
Light Requirements
Lupinus arcticus S. Wats. ssp. arcticus grows best in full sun. It requires at least 6-8 hours of direct sunlight every day to thrive. Plants that receive inadequate sunlight are likely to develop poor branching and bear fewer flowers.
Temperature Requirements
This plant is adapted to the harsh climatic conditions of the Arctic and sub-Arctic regions. It can survive in temperatures as low as -40°C during the winter months. However, during the growing season, a temperature range of 10 to 20°C is ideal for optimal growth and flowering. Extreme temperature fluctuations, especially above 25°C, can negatively affect the plant's growth and development.
Soil Requirements
Lupinus arcticus S. Wats. ssp. arcticus requires well-drained soil that is rich in organic matter. The soil should have a neutral to slightly acidic pH range of 6.0 to 7.5. Plants can tolerate a wide range of soil textures, from sandy loam to gravelly soils. However, they do not perform well in heavy clay soils or compacted soil, which can inhibit root growth. It is important to note that this plant is sensitive to high levels of salts and may require frequent watering in areas with high salt concentrations in the soil.
Cultivation Methods for Lupinus arcticus S. Wats. ssp. arcticus
Lupinus arcticus S. Wats. ssp. arcticus is a hardy perennial plant that is native to the colder climates of North America, specifically the Arctic regions. It can be propagated by seed or by division of established clumps in early spring or autumn. The plant prefers to grow in full or partial sun, in well-draining soil that is slightly acidic to neutral pH. It also prefers a cool climate and is best grown in USDA Hardiness zones 1 to 6.
Watering Needs for Lupinus arcticus S. Wats. ssp. arcticus
Lupinus arcticus S. Wats. ssp. arcticus requires consistent moisture in order to thrive. During the growing season, the plant should be watered whenever the soil feels dry to the touch. However, the soil should not be allowed to become waterlogged as this can lead to root rot. When watering, it is best to use a soaker hose or a watering can to ensure that the water reaches the roots without splashing the foliage.
Fertilization for Lupinus arcticus S. Wats. ssp. arcticus
Lupinus arcticus S. Wats. ssp. arcticus prefers nutrient-rich soil that has been supplemented with organic matter. A balanced fertilizer with an NPK ratio of 10-10-10 can be applied in the early spring before new growth appears. An additional application of fertilizer can be made in early summer to encourage strong growth and flowering.
Pruning for Lupinus arcticus S. Wats. ssp. arcticus
Pruning Lupinus arcticus S. Wats. ssp. arcticus is not necessary, but the plant can benefit from deadheading spent flowers. This encourages the plant to produce new blooms and also prevents self-seeding, which can lead to an overgrowth of the plant. Deadheading can be done by simply cutting off the spent flowers with a pair of garden shears.
Propagation of Lupinus arcticus S. Wats. ssp. arcticus
Lupinus arcticus, commonly known as Arctic Lupine, is a perennial herbaceous plant that is native to North America. The plant is usually propagated by seeds, although tissue culture techniques can also be used.
Propagation by Seeds
The propagation of Lupinus arcticus by seeds is a simple process. The seeds can be sown directly into the soil where the plant is to grow, or they can be started indoors and then transplanted.
When sowing seeds directly into the soil, it is important to prepare the ground by removing any weeds and loosening the soil. The seeds must be sown at a depth of about ¼ inch, and they should be spaced about 6 inches apart. The soil should be kept moist until the seedlings emerge.
If starting the seeds indoors, it is recommended to do so about 6-8 weeks before the last frost. The seeds should be sown in pots or trays filled with a well-draining potting mix. The pots or trays should be kept in a warm and bright location, and the soil should be kept moist. Once the seedlings have emerged, they can be transplanted outdoors after the last frost.
Tissue Culture Techniques
Tissue culture techniques can also be used to propagate Lupinus arcticus. This method involves growing the plant from a small piece of tissue, such as a leaf or stem, that has been taken from the parent plant. The tissue is placed in a nutrient-rich medium that encourages the growth of new plants.
Tissue culture techniques can be useful for producing large numbers of genetically identical plants, but the process is more complex and requires specialized equipment and expertise.
Disease and Pest Management for Lupinus arcticus S. Wats. ssp. arcticus
Lupinus arcticus S. Wats. ssp. arcticus, commonly known as Arctic lupine, is a native perennial herb that is commonly found in alpine and subalpine areas. However, like all plants, Arctic lupine is susceptible to various diseases and pests that may cause damage to the plant and lead to reduced yields. Here are the common diseases and pests that affect Arctic lupine and ways to manage them.
Diseases
One of the diseases that affect Arctic lupine is root rot. It is caused by a soil-borne fungus that infects the roots of the plant, leading to stunted growth, yellow foliage, and death. The disease thrives in poorly drained soils and areas where moisture is excessive. To manage the disease, it is advisable to plant disease-resistant cultivars and to ensure proper drainage of the soil.
Another disease that affects Arctic lupine is powdery mildew. It is caused by a fungal infection that appears as a white or grayish powdery growth on the leaves, stems, and flowers of the plant. The disease can cause significant damage to the plant and may lead to reduced yields. To manage the disease, it is advisable to avoid overhead irrigation, improve air circulation around the plant, and apply fungicides when necessary.
Pests
One of the common pests that affect Arctic lupine is the lupine aphid. It feeds on the sap of the plant and causes yellowing of the foliage, stunted growth, and reduced yields. To manage the pest, it is advisable to plant resistant cultivars, apply insecticidal soaps or oils when necessary, and encourage the presence of beneficial insects that prey on the aphids.
The lupine weevil is another major pest that affects Arctic lupine. The larvae of the weevil feed on the roots of the plant, leading to stunted growth, reduced yields, and eventual death. To manage the pest, it is advisable to remove infected plants, plant early in the season to avoid infestations, and apply insecticides when necessary.
Regular scouting and monitoring of the plant for disease and pest problems is essential in managing them effectively. Proper cultural practices such as planting disease-resistant cultivars, ensuring proper drainage, and avoiding overhead irrigation can also help prevent disease and pest problems in Arctic lupine.
