Origin
Thelypodium howellii S. Wats. ssp. spectabilis (M.E. Peck) Al-Shehbaz is a perennial plant that belongs to the family Brassicaceae. It is native to North America and can be found in states like California, Nevada, and Oregon.
Common Names
The plant is commonly known as Howell's spectacular thelypody. Other names include the Nevada mustard, Yamhill spectacular thelypody, and the spectacular thelypody.
Uses
Thelypodium howellii S. Wats. ssp. spectabilis has been used for ornamental purposes due to its attractive appearance. Its foliage and clusters of flowers attract pollinators, making it an essential plant in ecosystems. Additionally, it has been used for medicinal purposes in Native American culture.
General Appearance
The plant usually grows to a height of about 50cm and has a distinct erect stem. Its leaves are lance-shaped, about 6-20cm long, and typically gray-green. The flowers are clustered in a terminal inflorescence, with each blossom measuring about 2-4mm wide. The petals are white, and the sepals are greenish-yellow or purplish.
Light Requirements
Thelypodium howellii ssp. spectabilis grows best in full sun to partial shade, receiving at least 6 hours of direct sunlight per day. However, it can tolerate some shade, especially in hotter climates, as long as it still receives adequate light.
Temperature Requirements
This plant is native to the Pacific Northwest, where it grows in cool, moist habitats. It prefers moderate temperatures between 55-75°F (13-24°C) during the growing season, but can tolerate temperatures as low as 28°F (-2°C) and as high as 90°F (32°C).
Soil Requirements
Thelypodium howellii ssp. spectabilis prefers well-draining soils that are rich in organic matter. It can tolerate a variety of soil textures, but grows best in moist, loamy soils with a neutral to slightly acidic pH between 6.0-7.0. It is important to keep the soil evenly moist, but avoid waterlogged conditions.
Cultivation Methods
Thelypodium howellii S. Wats. ssp. spectabilis (M.E. Peck) Al-Shehbaz, commonly known as Spectacular Thelypody, is a herbaceous perennial plant that can be grown successfully in USDA hardiness zones 4 to 8. This plant prefers full sun but can tolerate partial shade with well-draining soil. The soil type should be moderately rich in organic matter and slightly acidic with pH ranging between 5.5 to 6.5. Seeds can be sown directly in the ground in the fall or winter, or in early spring.
Watering Needs
The Spectacular Thelypody plant requires moderate watering, especially during the growing season. It is best to water the plant deeply once a week, allowing the soil to dry somewhat before the next watering. During hot weather, it may be necessary to water more frequently to prevent the soil from becoming too dry. Avoid overwatering, as this can result in root rot, which is detrimental to the plant's health.
Fertilization
Thelypodium howellii S. Wats. ssp. spectabilis (M.E. Peck) Al-Shehbaz, benefit from annual fertilization, which should be done in early spring and late summer. A balanced fertilizer with equal parts of nitrogen, phosphorus, and potassium is recommended. Alternatively, you can use compost or well-rotted manure to enrich the soil. Avoid high-nitrogen fertilizers, as this can cause excessive foliage growth at the expense of flower production.
Pruning
Pruning is not essential for Spectacular Thelypody, but it can help to keep the plant looking tidy and promote healthy growth. Deadheading of spent flowers stimulates the production of new blooms and prevents the plant's energy from being diverted into seed production. Cut back the entire plant to the ground level in late fall or early winter after the first frost occurs. This will help the plant to prepare for the dormant winter period and encourage vigorous regrowth in spring.
Propagation of Thelypodium howellii S. Wats. ssp. spectabilis (M.E. Peck) Al-Shehbaz
Thelypodium howellii S. Wats. ssp. spectabilis (M.E. Peck) Al-Shehbaz or the showy rockcress is a beautiful plant that can be propagated by seed or vegetatively.
Propagation by Seed
Propagation of Thelypodium howellii S. Wats. ssp. spectabilis by seed is relatively easy. The seeds can be sown directly in the garden in the fall or early spring. The soil should be well-drained and slightly acidic, with a pH between 6.0 and 7.0. The seeds should be lightly covered with soil and kept moist until they germinate. Germination usually occurs within four to six weeks.
Seedlings should be thinned to a distance of at least 24 inches apart once they reach a height of three to four inches. They can be fertilized with a balanced fertilizer once they are established.
Vegetative Propagation
Thelypodium howellii S. Wats. ssp. spectabilis can also be propagated vegetatively. The plant can be divided in the early spring or fall. The root ball should be gently loosened, and the plant should be separated into smaller clumps with a sharp knife or garden shears. Each clump should have several healthy leaves and roots. The clumps can be replanted in well-drained soil and lightly watered.
The mother plant should be watered well after dividing it to help it recover from the stress of being divided. The newly planted clumps should be kept moist and protected from strong winds and direct sunlight for the first few weeks after planting. They can be fertilized with a balanced fertilizer once they are established.
Overall, Thelypodium howellii S. Wats. ssp. spectabilis is a beautiful plant that can be propagated easily by seed or vegetative means.
Disease Management
Thelypodium howellii ssp. spectabilis is not known to be affected by any serious diseases. However, the plant might occasionally be affected by fungi, such as powdery mildew and rust.
To prevent powdery mildew, it is important to maintain good air circulation around the plants and avoid overhead watering. Remove any affected leaves immediately and dispose of them to prevent the spread of the fungus. Applying fungicides, such as sulfur or potassium bicarbonate, can also help to control powdery mildew.
Rust can be controlled by similar methods as well. Prevention is key, as there are no known chemicals to control rust in Thelypodium howellii ssp. spectabilis. Keep the plant well-ventilated and remove any infected leaves immediately. Applying fungicides, such as copper-based solutions, can also help to control rust.
Pest Management
Thelypodium howellii ssp. spectabilis is generally pest-free. However, in some instances, the plant might fall prey to chewing insects such as caterpillars and beetles.
To control caterpillars, handpick them off the plant and dispose of them immediately. Applying Bacillus thuringiensis (Bt) can also be effective in controlling caterpillar infestations.
Beetles can be controlled by applying insecticides, such as spinosad or neem oil. Handpicking them off the plant and disposing of them can also be effective, especially if their numbers are small.
Regularly monitoring the plants for any signs of infestation can also help prevent pest problems from escalating. It is important to keep the area around the plants free of debris and weeds to prevent pest habitats from forming.
