Plant Description
Thelypodium lasiophyllum (Hook. & Arn.) Greene var. inalienum B.L. Robins. is a perennial herbaceous plant belonging to the mustard family (Brassicaceae). It is native to the western United States, specifically the Great Basin and Colorado Plateau regions.
Common Names
Thelypodium lasiophyllum is commonly known as western mustard or hairy stem mustard.
Uses
Although Thelypodium lasiophyllum has no significant commercial value, it has important ecological significance. The plant plays a crucial role in providing food and habitat for various wildlife species, including deer, elk, and small mammals. Additionally, Thelypodium lasiophyllum has historically been used by some indigenous groups for medicinal purposes.
General Appearance
Thelypodium lasiophyllum has a basal rosette of leaves from which multiple flowering stems emerge, typically reaching a height of 1 to 3 feet. The leaves are hairy and oblong to lanceolate in shape, with toothed edges. The flowers are small, white to pink in color, and arranged in elongated clusters at the end of each stem. The plant prefers dry, rocky or gravelly soil in sagebrush flats, pinyon-juniper woodlands, and conifer forests.
Light Requirements
Thelypodium lasiophyllum typically grows in full sun to partial shade. In areas with hot summers, it may benefit from some afternoon shade to avoid heat stress. However, too much shade can lead to weak stem growth and poor flowering.
Temperature Requirements
This plant is adapted to a wide range of temperatures, from cool mountain regions to hot desert valleys. However, it grows best in areas with a moderate climate, where temperatures do not exceed 80°F (27°C) during the day and do not drop below 40°F (4°C) at night.
Soil Requirements
Thelypodium lasiophyllum prefers well-drained soils with a neutral to slightly alkaline pH (6.5-7.5). It can tolerate a range of soil textures, from sandy to clayey, as long as the water does not accumulate excessively in the roots. It also benefits from the presence of organic matter, which helps retain moisture and nutrients in the soil.
Cultivation Methods
Thelypodium lasiophyllum (Hook. & Arn.) Greene var. inalienum B.L. Robins. is a perennial plant that is found in the western regions of North America. This plant can thrive in a variety of soil types. However, it prefers well-drained soil that has a neutral to slightly alkaline pH. It can grow in areas with full sun to partial shade.
Propagation can be done through seed or division of the root system. The seeds should be sown in the early spring or fall, as it needs a cold period to germinate. The plants grow best where the climate is temperate to cold and are hardy to USDA zones 3 to 9.
Watering Needs
During the initial establishment of Thelypodium lasiophyllum, it is necessary to keep the soil consistently moist. However, once the plant is mature, it is drought tolerant and needs watering only when the soil is dry to the touch. Overwatering can cause root rot and reduce the plant's ability to withstand colder temperatures.
Fertilization
The plant does not require significant fertilization. It can survive with minimal fertilization levels, but to ensure optimal growth and healthy foliage, apply a balanced fertilizer during the growing season. Over-fertilizing can lead to excessive vegetative growth, which may make the plant vulnerable to wind damage.
Pruning
Thelypodium lasiophyllum does not require regular pruning. However, if there are damaged or diseased parts, they need to be removed promptly to prevent the spread of the condition. Aside from this, the plant can undergo rejuvenation pruning every three to four years. This process involves removing up to one-third of the plant's stems, promoting the growth of new foliage and flowers.
Propagation of Thelypodium lasiophyllum (Hook. & Arn.) Greene var. inalienum B.L. Robins.
Thelypodium lasiophyllum (Hook. & Arn.) Greene var. inalienum B.L. Robins. can be propagated through seeds and cuttings.
Propagation through Seeds
The seeds of Thelypodium lasiophyllum (Hook. & Arn.) Greene var. inalienum B.L. Robins. can be sown directly into the ground or in containers filled with well-draining soil. The ideal time for sowing the seeds is in the fall, after the last frost date.
It is important to provide the seeds with consistent moisture until they germinate. Once the seedlings have grown a few inches tall, they can be transplanted into larger containers or outdoors in their permanent location.
Propagation through Cuttings
Thelypodium lasiophyllum (Hook. & Arn.) Greene var. inalienum B.L. Robins. can also be propagated through cuttings taken from the plant. Take a cutting from the plant in the spring, using sharp and clean shears. Choose a healthy stem that is several inches long and has new growth at the tip.
Remove the leaves from the bottom half of the cutting, and dip the cut end of the stem into a rooting hormone. Then, place the cutting in a well-draining potting soil and water it. Keep the soil moist and place the pot in a warm, bright location. After a few weeks, the cutting should develop roots and can be transplanted into a larger container or into its permanent location outdoors.
Disease and Pest Management for Thelypodium lasiophyllum
Thelypodium lasiophyllum is a native plant to the western United States and is generally hardy. However, there are a few common diseases and pests that can affect this plant. Here are some tips for managing them:
Diseases
The most common disease that affects Thelypodium lasiophyllum is powdery mildew. This fungal disease presents as a white, powdery substance on the leaves and stems of the plant. To manage powdery mildew, you should:
- Remove and discard affected plant material
- Avoid overhead watering to decrease the plant's humidity level
- Apply a fungicide as recommended by a local gardening or agricultural extension office
Another disease that can affect Thelypodium lasiophyllum is clubroot. This soil-borne disease presents as swollen and distorted roots and can lead to stunted growth and even death if left unchecked. To prevent clubroot, make sure to rotate your crops and avoid planting members of the mustard family in the same area for at least two years. If clubroot is present, remove and discard affected plants and avoid using that soil for susceptible plants in the future.
Pests
Thelypodium lasiophyllum can also be affected by a few pests, such as aphids and flea beetles.
Aphids are small, soft-bodied insects that suck sap from the plant, causing yellowing and wilting. To manage aphids, you can:
- Blast them off the plant with a strong stream of water
- Introduce natural predators, such as ladybugs or lacewings
- Apply an insecticidal soap or oil as recommended by a local gardening or agricultural extension office
Flea beetles are small, jumping insects that create small holes in the leaves of the plant. To manage flea beetles, you can:
- Introduce natural predators, such as predaceous ground beetles or parasitic wasps
- Apply a repellent, such as neem oil or kaolin clay
- Use floating row covers to physically exclude the beetles from the plants
By following these tips, you can help prevent and manage diseases and pests that might affect Thelypodium lasiophyllum.
