Origin
Thelypodium rhomboideum Greene var. gracilipes, commonly known as slender-stemmed thelypody, is a plant species that belongs to the Brassicaceae or mustard family. It is native to North America and can be found in the western regions of the United States and Canada.
Common Names
Aside from the common name "slender-stemmed thelypody," Thelypodium rhomboideum Greene var. gracilipes is also known by other common names such as "slenderstem thelypody" and "diamondleaf thelypody."
Uses
Thelypodium rhomboideum Greene var. gracilipes is known for having edible roots that were used for food by indigenous tribes such as the Shoshone and Paiute. The roots are high in starch and were often boiled or roasted before being consumed. Today, the plant is mostly used for ornamental purposes and is often cultivated as a garden plant or used in landscape design.
General Appearance
Thelypodium rhomboideum Greene var. gracilipes is a perennial plant that grows up to a height of 60 centimeters. It has slender stems that are finely pubescent and sometimes branched. The leaves are alternate, with blades that are diamond-shaped and have serrated edges. The flowers of the plant are typically white or pink in color and are arranged in loose clusters at the top of the stems. The fruit is a slender pod that is 2-6 centimeters long and contains seeds that are small, black, and shiny.
Light requirements
Thelypodium rhomboideum Greene var. gracilipes prefers a sunny location and can tolerate partial shade. It grows best when exposed to full sun for at least six hours daily.
Temperature requirements
The plant is adapted to a wide range of temperatures and can grow in cool-to-cold and warm-to-hot climates. Optimal temperatures for its growth range from 15°C to 25°C. The plant can also tolerate temperatures as low as -20°C.
Soil requirements
The plant prefers well-drained soils that are rich in organic matter, but can also grow in sandy or rocky soils. The soil pH range should be slightly acidic to neutral, around 6.0-7.5. Additionally, the soil must be moist, but not waterlogged as it can lead to root rot and other diseases.
Cultivation Methods
Thelypodium rhomboideum var. gracilipes requires well-drained soil and a location that receives full or partial sunlight. This plant can withstand drought-like conditions but cannot tolerate excessive moisture. It grows well in USDA hardiness zones 6 to 9.
Watering Needs
This plant requires moderate watering. Water the plant deeply once every 7-10 days, allowing the soil to dry out between watering sessions. During the growing season, the plant may require extra watering if the weather is hot and dry.
Fertilization
The soil in which Thelypodium rhomboideum var. gracilipes grows should have a pH between 6.0 and 7.0. Apply a balanced fertilizer, such as a 10-10-10 fertilizer, in early spring. Avoid applying fertilizer during the growing season, as this can encourage rot root growth.
Pruning
Pruning is not usually necessary for this plant. It has a natural mounding habit and generally needs no shaping. However, if you want a more compact plant, prune it in early spring before new growth emerges. Cut back any stems that have become too long or leggy. This plant may self-seed if you do not deadhead it. Therefore, if you do not want it to spread, consider deadheading it regularly.
Propagation of Thelypodium rhomboideum Greene var. gracilipes (B.L. Robins.) Payson
Thelypodium rhomboideum Greene var. gracilipes (B.L. Robins.) Payson, commonly known as the Sanddune Pennyroyal, can be propagated through several methods including seed propagation and vegetative propagation.
Seed Propagation
Seed propagation is the most common and efficient method to propagate Thelypodium rhomboideum Greene var. gracilipes (B.L. Robins.) Payson. The seeds should be sown in a well-drained soil mix with a good amount of organic matter. The seeds are very tiny and should be sowed shallow on the media surface. They should be moistened regularly until germination occurs which usually takes 10-21 days. Germination can be improved by stratification, which involves storing the seeds in a refrigerator for a period of about 4-6 weeks before planting.
Vegetative Propagation
Thelypodium rhomboideum Greene var. gracilipes (B.L. Robins.) Payson can also be propagated through vegetative propagation. Cuttings can be taken from the plant and planted in well-drained soil mix with a good amount of organic matter. Rooting hormone can be used to encourage rooting. The cuttings should be kept moist and shaded until they are established. Division is another vegetative propagation method that can be used for this plant. The plant can be divided in spring by carefully separating the root ball into smaller sections and planting them in well-drained soil mix.
Disease Management
Thelypodium rhomboideum Greene var. gracilipes (B.L. Robins.) Payson plant is susceptible to diseases like Leaf Spot, Powdery Mildew, and Verticillium Wilt.
Leaf Spot: This fungal disease causes yellow spots on the leaves which eventually turn brown and can even destroy the whole leaf. To manage Leaf Spot, remove the infected leaves and spray the plant with a fungicide.
Powdery Mildew: This fungal disease causes white powdery spots on the leaves. To manage Powdery Mildew, remove the infected leaves, increase air circulation around the plant, and spray the plant with a fungicide.
Verticillium Wilt: This soil-borne disease causes yellowing and wilting of the leaves and stems. To manage Verticillium Wilt, remove the infected plant and treat the soil with a fungicide.
Pest Management
Thelypodium rhomboideum Greene var. gracilipes (B.L. Robins.) Payson plant is susceptible to pests like Aphids and Cabbage Worms.
Aphids: These small insects suck the plant sap, causing leaves curling. To manage Aphids, spray the plant with a strong blast of water or introduce beneficial insects like ladybugs and lacewings.
Cabbage Worms: These pests consume leaves and create holes in them. To manage Cabbage Worms, handpick them or spray the plant with insecticide.
