Origin
Lupinus sparsiflorus Benth. var. inopinatus C.P. Sm. is a subspecies of the plant Lupinus sparsiflorus Benth. It is native to North America, specifically in the western United States where it is found in dry, rocky areas in California, Nevada, Oregon, and Utah.
Common Names
The subspecies is commonly known as Surprise Valley lupine, Inyo lupine, and Inyo-White Mountains lupine.
Uses
Lupinus sparsiflorus Benth. var. inopinatus C.P. Sm. is commonly used for erosion control, rangeland improvement, and as a source of forage for wildlife and livestock. The plant is also used in traditional Native American medicine to treat skin conditions, rheumatism, and respiratory illnesses.
General Appearance
Lupinus sparsiflorus Benth. var. inopinatus C.P. Sm. is a perennial herb that grows up to 60 cm tall. It has blue or lavender flowers that bloom from April to September and are arranged in dense spikes. The leaves are palmately compound and mostly basal, with leaflets that are oblong to fan-shaped and up to 4 cm long. The plant has a taproot and stems that are covered in short hairs.
Light Requirements
Lupinus sparsiflorus Benth. var. inopinatus C.P. Sm. prefers to grow in full sun or partially shaded areas. In areas with high-intensity sunlight, it requires some shade during the hottest periods of the day. However, it must receive a minimum of 6 hours of full sun exposure. Therefore, planting this species where it will get direct sunlight should be a priority.
Temperature Requirements
This plant species is adapted to hot and dry environments. In its natural habitat, it grows in regions with a warm Mediterranean climate. During its growing season, it thrives in temperatures that range between 22 and 32 °C (72 and 90 °F). The climate needs to be dry, and moderate humidity is essential. The plants will not tolerate extreme cold temperatures or frost.
Soil Requirements
Lupinus sparsiflorus Benth. var. inopinatus C.P. Sm. is well adapted to soils with excellent drainage. It prefers gravelly and sandy soils, which have a neutral to slightly acidic pH level ranging from 6.5 to 7.5. Good soil fertility is essential, and the soil must be well-aerated to encourage optimal plant growth. However, it can survive in less fertile soils as long as compost or other organic matter is added during planting.
Cultivation Methods
Lupinus sparsiflorus Benth. var. inopinatus C.P. Sm. can be grown from seed or transplanted seedlings. For seed propagation, sow seeds in well-drained soil with a pH of 6.0-7.0. Cover the seeds with ¼ inch of soil and water lightly. Germination typically occurs in 14-21 days. For transplanting, start seedlings indoors and transplant to the garden after the last frost. Lupinus sparsiflorus Benth. var. inopinatus C.P. Sm. grows well in full sun to partial shade and prefers well-drained soil.
Watering Needs
Lupinus sparsiflorus Benth. var. inopinatus C.P. Sm. has medium water requirements and prefers evenly moist soil. Water deeply once a week or more often during hot, dry weather. Avoid overwatering, as this can lead to root rot. Mulch around the base of the plant to help retain soil moisture and suppress weeds.
Fertilization
Fertilize Lupinus sparsiflorus Benth. var. inopinatus C.P. Sm. with a balanced fertilizer such as 10-10-10 in early spring, just before new growth appears. Repeat every 4-6 weeks during the growing season. Be careful not to overfertilize, as this can cause excessive foliage growth and reduced flower production.
Pruning
Prune Lupinus sparsiflorus Benth. var. inopinatus C.P. Sm. after the blooming season to remove spent flower spikes and encourage bushy growth. Cut back the stems to just above the basal foliage. This will help to promote a second flush of flowers later in the season. Avoid cutting back into bare wood, as this can damage the plant and reduce its vigor.
Propagation of Lupinus sparsiflorus Benth. var. inopinatus C.P. Sm.
Lupinus sparsiflorus Benth. var. inopinatus C.P. Sm., commonly known as the surprise lupine, can be propagated through seeds or cuttings. However, seed propagation is the widely used method for this plant species.
Seed propagation
Before planting the seeds, they should be scarified to crack their hard outer shell. Scarification can be done by manually filing the seed coat or soaking the seeds in hot water for 24 hours before planting. After scarification, the seeds should be planted 1-2 inches deep in a well-draining soil mix in pots or seed trays. The pots or trays should be placed in a sunny location, and the soil should be kept moist.
The seedlings should start emerging from the soil within 2-4 weeks after planting. Once the seedlings have reached a height of 3-4 inches and have two sets of true leaves, they can be transplanted into bigger containers or directly into the ground. Transplanting should be done carefully to avoid disturbing the roots.
Cutting propagation
Lupinus sparsiflorus Benth. var. inopinatus C.P. Sm. can also be propagated through stem cuttings. The cuttings should be taken from new growth in the spring or early summer. The cuttings should be 3-4 inches long and should have at least two nodes. Remove the lower leaves from the cutting and dip the cut end in rooting hormone. Plant the cutting in a well-draining soil mix and keep it moist. Covering the pot with plastic can help retain moisture around the cutting. Roots should start forming within 2-3 weeks. Once the cutting has established roots, it can be transplanted into a bigger container or planted directly into the ground.
Disease Management
Lupinus sparsiflorus Benth. var. inopinatus C.P. Sm. is susceptible to a few diseases that can impact the plant's health and reduce its growth and yield. Managing these diseases is essential to maintain plant health and ensure maximum production. Some of these common diseases are:
Anthracnose
Anthracnose is a fungal disease that affects the leaves, stem, and flowers of the plant. It causes dark, sunken spots on the leaves and stems, which can spread and cause the plant to wither and die. To manage anthracnose, remove and destroy any infected plant parts, and use fungicides to prevent further spread.
Fusarium wilt
Fusarium wilt is a fungal disease that affects the plant's vascular system, causing wilting, yellowing, and death. To manage Fusarium wilt, practice crop rotation, remove infected plants promptly, and use resistant varieties of the plant.
Pest Management
Lupinus sparsiflorus Benth. var. inopinatus C.P. Sm. is also susceptible to several pests that can cause significant damage to the plant, impacting yield and overall plant health. Managing these pests is essential to maintain plant health and ensure maximum production. Some common pests that can affect this plant are:
Aphids
Aphids are small, soft-bodied insects that suck the sap from the plant, causing stunted growth, wilting, and leaf curling. To manage aphids, use insecticidal soap or horticultural oils, or introduce natural predators like ladybugs and lacewings.
Spider mites
Spider mites are tiny pests that feed on the plant's sap and cause yellowing and bronzing of the leaves. To manage spider mites, use a high-pressure spray of water to remove them from the plant, or apply insecticidal soap or horticultural oils. Introduce natural predators like ladybugs and lacewings can also help control spider mites.
Implementing proper disease and pest management strategies is crucial for maintaining the health and yield of Lupinus sparsiflorus Benth. var. inopinatus C.P. Sm. plants. By staying vigilant and responding promptly to any signs of disease or infestation, you can keep your plants thriving and productive.
