Overview:
Penstemon thompsoniae (Gray) Rydb. var. desperatus Neese, also known as Thompson's beardtongue or Desperate Penstemon, is a perennial plant native to the western United States. It belongs to the family Plantaginaceae and is known for its showy, tubular flowers that attract pollinators such as hummingbirds, bees, and butterflies.
Description:
The Desperate Penstemon plant typically grows between 12 and 24 inches tall and spreads 12 to 18 inches wide. Its leaves are narrow and lance-shaped, ranging in color from green to grayish-green. The plant produces long, upright stems with many small, funnel-shaped flowers that are bright pink to purple in color, blooming from May to June. The flowers have five lobes and are up to 1.5 inches long with a long protruding stamen.
Origin:
The natural range of the Desperate Penstemon plant is the Great Basin region of the western United States, including parts of California, Nevada, and Utah. It typically grows in rocky, well-drained soils at higher elevations, ranging from 4,000 to 9,000 feet.
Common Names:
Desperate Penstemon and Thompson's beardtongue are the common names for Penstemon thompsoniae (Gray) Rydb. var. desperatus Neese.
Uses:
The Desperate Penstemon plant is primarily grown in gardens as an ornamental for its showy flowers and attractive foliage. It is also useful in native plant gardens and restoration projects due to its ability to attract pollinators and thrive in dry, rocky soils. However, it is important to note that the plant is protected and limited to only a few locations due to its threatened status.
Light Requirements
Penstemon thompsoniae var. desperatus typically prefers full sun exposure to partial shade. It is suitable for planting in areas with direct sunlight as long as the soil remains adequately moist. The plant can adapt to partially shaded conditions, but it may lead to decreased blooming and overall growth.
Temperature Requirements
The plant is native to the desert grasslands of western North America, where it thrives in typical desert-like hot and dry conditions. It can tolerate temperature ranges between 10°F to 80°F (-12°C to 27°C). The plant can also handle some occasional frost, but prolonged exposure to below-freezing temperatures can damage the foliage, leading to stunted growth and decreased flowering.
Soil Requirements
Penstemon thompsoniae var. desperatus prefer well-draining, sandy, or gravelly soils with pH levels between 5.5 and 7.5. The plant can grow in slightly alkaline or slightly acidic soils. The soil must remain moderately moist to dry, and the soil fertility level should range from poor to low. Too high a level of soil fertility can cause excessive vegetative growth, leading to lower flower production.
Cultivation Methods
Penstemon thompsoniae (Gray) Rydb. var. desperatus Neese is a small perennial plant that is native to North America. It prefers well-draining soil that is rich in organic matter. It grows best in full sunlight or partial shade and can tolerate drought conditions.
To cultivate this plant, prepare the soil by adding compost and other organic matter to increase its fertility. Plant the Penstemon thompsoniae (Gray) Rydb. var. desperatus Neese seedlings in the soil during the spring season, at a depth of 1-2 inches, and space each plant 10-12 inches apart. Water the soil well after planting.
Watering Needs
The Penstemon thompsoniae (Gray) Rydb. var. desperatus Neese prefers well-draining soil, but it needs regular watering to thrive. It is essential to water the soil deeply once or twice a week in the absence of rainfall, allowing the water to soak down to the plant's roots.
Avoid excessively watering the soil, as it can lead to root rot and other fungal diseases. Ensure that the plant's surrounding soil is damp, but not waterlogged, to prevent the onset of fungal diseases.
Fertilization
The Penstemon thompsoniae (Gray) Rydb. var. desperatus Neese does not require frequent fertilization. However, applying fertilizer in the spring can promote healthy growth and blooming.
Use a balanced fertilizer with equal amounts of nitrogen, phosphorus, and potassium. Apply the fertilizer to the soil surrounding the plant and avoid getting it on the leaves or stem. Water the soil well after fertilizing.
Pruning
Pruning the Penstemon thompsoniae (Gray) Rydb. var. desperatus Neese can help to maintain its shape and promote blooming. It is best to prune the plant during the late summer months after it has finished flowering.
Using clean pruning shears, remove any wilted or diseased portions of the plant. Cut back the stems to 2-3 inches above the ground level to encourage new growth and blooming the following season.
Propagation methods for Penstemon thompsoniae (Gray) Rydb. var. desperatus Neese
Penstemon thompsoniae (Gray) Rydb. var. desperatus Neese, also known as Thompson's beardtongue, is a herbaceous perennial plant that is native to North America. The plant produces showy flowers on tall, slender stems that make it a popular choice for gardeners. Propagation of the plant can be achieved through several methods, including:
Seed propagation
Seed propagation is the most common method used to propagate Penstemon thompsoniae var. desperatus Neese. Seeds can be collected from the plant when the seedpods are ripe, which is usually in late summer or early fall. The collected seeds should be dried, cleaned, and stored in a cool, dry place until they are ready to be sown.
Before sowing the seeds, the soil should be prepared by removing any weeds and debris and loosening the soil to facilitate good drainage. The seeds can be sown directly into the soil or started indoors under grow lights. If sowing indoors, the young plants should be gradually acclimated to outdoor conditions before transplanting.
Division
Penstemon thompsoniae var. desperatus Neese can also be propagated through division. This method involves separating the plant's root ball into smaller sections and planting each section into a new location. Division is best done in the spring or fall when the plant is not actively growing.
To divide the plant, gently dig up the root ball with a spade or garden fork and shake off any excess soil. Use a knife or scissors to cut the root ball into sections, making sure that each section has at least one healthy shoot. Replant each section in a well-prepared location and water thoroughly.
Stem cuttings
Stem cuttings can also be used to propagate Penstemon thompsoniae var. desperatus Neese. This method is best done in the summer when the plant is actively growing. Select a healthy stem and use a sharp knife or scissors to take a cutting that is 3-4 inches long.
Remove the lower leaves from the cutting and dip the cut end into a rooting hormone to encourage root growth. Plant the cutting into a well-draining soil mix and keep it moist until roots form. Once roots have formed, transplant the young plant into a well-prepared location in the garden.
Disease Management
Penstemon thompsoniae (Gray) Rydb. var. desperatus Neese is typically a healthy plant, but like any other plant, it may fall victim to certain diseases. Here are some of the common diseases that may affect Penstemon thompsoniae and how to manage them:
Crown Rot
Crown rot is a soil-borne fungal disease that can cause the entire plant to wilt and die. It is usually caused by overwatering and poor drainage. To manage this disease, avoid overwatering the plants and improve the soil drainage. You can also apply fungicides to prevent the spread of the disease.
Leaf Spot
Leaf spots are caused by fungal or bacterial infections that result in the yellowing and browning of leaves. To manage this disease, remove and destroy any infected leaves, and avoid overhead watering. Apply fungicides to prevent the spread of the disease.
Powdery Mildew
Powdery mildew is a fungal disease that appears as a white powdery substance on the leaves, stems, and flowers of the plant. To manage this disease, avoid overhead watering, remove and destroy any infected plant parts, and apply fungicides.
Pest Management
Penstemon thompsoniae (Gray) Rydb. var. desperatus Neese is relatively pest-free. However, here are some of the common pests that may affect the plant and how to manage them:
Aphids
Aphids are small, soft-bodied insects that suck the sap from the plants. They usually appear on the new growth of the plant. To manage this pest, you can use insecticidal soap, neem oil, or horticultural oil.
Spider Mites
Spider mites are tiny, eight-legged pests that suck the plant's sap, causing the leaves to turn yellow and dry. To manage this pest, increase the humidity around the plant by misting it regularly. You can also use insecticidal soap or neem oil to control the spider mites.
Thrips
Thrips are small, slender insects that damage the foliage and flowers of the plant. They suck the sap and scrape the leaves, causing them to curl and turn brown. To manage this pest, you can use insecticidal soap, neem oil, or horticultural oil.
