Origin
The Draba asprella Greene var. stelligera O.E. Schulz is a herbaceous flowering plant that belongs to the mustard family, Brassicaceae. This plant is native to the Rocky Mountains of North America.
Common Names
This plant is commonly known as the Rocky Mountain whitlow-grass, or Stellate Whitlowgrass. The name "whitlowgrass" originated from its use as a folk remedy for whitlow, a painful infection around the nail or finger.
Uses
The Draba asprella Greene var. stelligera O.E. Schulz has been used traditionally as a medicinal plant for several centuries. Native American tribes commonly used this plant to treat skin infections, rheumatism, and tuberculosis. The plant is also used as a natural insecticide and fertilizer.
Today, the plant is mainly grown as an ornamental plant, mainly in rock gardens. It is known for its attractive, star-shaped yellow flowers that bloom in early spring.
General Appearance
The Draba asprella Greene var. stelligera O.E. Schulz is a low-growing, perennial plant that typically grows up to 10 cm high. The leaves of the plant are small and narrow, with a length of up to 2 cm. The plant produces small, yellow flowers, each with four petals, which grow in clusters at the end of each stem. The fruits of the plant are small capsules that contain numerous seeds. The plant prefers to grow in rocky or gravelly soils, in dry or alpine habitats.
Light Requirements
The plant Draba asprella Greene var. stelligera O.E. Schulz typically requires a full sun exposure for optimal growth. This plant thrives in direct sunlight for at least six hours per day and may not grow well in shaded areas.
Temperature Requirements
The plant Draba asprella Greene var. stelligera O.E. Schulz prefers cooler temperatures as it grows in alpine and subalpine areas. The average temperature needs to be between 5-10 degrees Celsius. This plant can tolerate extreme cold, but growth may be slow during freezing temperatures.
Soil Requirements
The plant Draba asprella Greene var. stelligera O.E. Schulz prefers moist soil that drains well. The soil must have good drainage to avoid waterlogging, which could lead to root rot. This plant can tolerate acidic or alkaline soils, but it grows best in a neutral to slightly alkaline pH. Additionally, the plant requires a rich soil that is high in organic matter to thrive.
Cultivation methods
Draba asprella Greene var. stelligera O.E. Schulz can be grown outdoors or indoors, depending on the climatic conditions. It grows best in well-drained soil that is rich in organic matter. The plant needs at least six hours of sunlight exposure daily, so make sure you plant it in a location that receives adequate sunlight.
Watering needs
Draba asprella Greene var. stelligera O.E. Schulz requires regular watering during its growing season. Water the plant deeply once a week during the growing season, but do not overwater it. Too much water can lead to root rot and other fungal diseases.
Fertilization
Draba asprella Greene var. stelligera O.E. Schulz requires regular fertilization to fuel its growth and promote blooming. Use a slow-release, balanced fertilizer with equal parts nitrogen, phosphorus, and potassium during the growing season. Follow the manufacturer's instructions to ensure the proper application rate.
Pruning
Draba asprella Greene var. stelligera O.E. Schulz doesn't require extensive pruning, but you can pinch off the dead flowers and leaves as you spot them. This will promote healthy growth, encourage blooming, and prevent the plant from looking unkempt. If the plant becomes too bushy, you can trim it down to size in the spring, before the growing season begins.
Propagation of Draba asprella Greene var. stelligera O.E. Schulz
Draba asprella Greene var. stelligera O.E. Schulz is a short-lived perennial plant that is primarily propagated by seed. The plant requires cold stratification to initiate germination. In addition to seed propagation, the plant can also be propagated vegetatively.
Seed Propagation
Seed propagation is the most common method used to propagate Draba asprella Greene var. stelligera O.E. Schulz. The seeds are relatively small and should be sown in the fall to ensure that they receive the required cold stratification period. The seeds can be sown directly into the ground or in a propagating tray filled with a well-draining potting mix.
It is important to keep the soil consistently moist while the seeds are germinating, which usually takes between 2-4 weeks. As the seedlings grow, they should be thinned to ensure that they have adequate space to develop. If the seedlings are started in a propagating tray, they should be transplanted into their permanent location in the spring.
Vegetative Propagation
While less common, Draba asprella Greene var. stelligera O.E. Schulz can also be propagated vegetatively. This method involves taking stem or leaf cuttings and rooting them to create a new plant. The cuttings should be taken from healthy plants during the growing season.
The cuttings can be rooted in a well-draining potting mix or directly in the ground if the soil is suitable. It is important to keep the cuttings consistently moist while they are rooting, and they may benefit from being covered to maintain a high level of humidity around them. Once the cuttings have rooted, they can be transplanted into their permanent location.
Disease and Pest Management for Draba asprella Greene var. stelligera O.E. Schulz
Draba asprella Greene var. stelligera O.E. Schulz is susceptible to various diseases and pests. Here are some of the most common ones and ways to manage them:
Diseases
Blackleg: This disease is caused by the fungus Phoma lingam. Symptoms include blackened and rotting stems and leaves. To manage blackleg, practice good sanitation by removing infected plant material and avoid overhead watering which promotes spore spread. Avoid planting in areas where Cruciferae crops have recently grown.
Clubroot: This disease is caused by the fungus Plasmodiophora brassicae. Symptoms include stunted growth, yellowed leaves, and swollen roots that cause plants to wilt and eventually die. To manage clubroot, practice good sanitation by removing infected plant material. Improve soil drainage and avoid acidic soils which favor the fungus. Crop rotation is also essential.
White Rust: This disease is caused by the fungus Albugo candida. Symptoms include yellowing leaves with white blisters on the lower surface. To manage white rust, practice good sanitation by removing infected plant material. Avoid overhead watering which promotes spore spread.
Pests
Cabbage Aphids: These pests are tiny insects that feed on the sap of the plant, causing distorted growth and yellowing leaves. To manage cabbage aphids, spray the plant with insecticidal soap or neem oil. Encourage natural predators like ladybugs and lacewings.
Cabbage Maggot: These pests are the larvae of the cabbage root fly and feed on the roots of the plant, causing stunted growth and wilting. To manage cabbage maggot, use floating row covers to prevent adult flies from laying eggs on the plant. Crop rotation and good sanitation (removing infected plant material) is also essential.
Imported Cabbageworm: These pests are the caterpillars of the white butterfly and feed on the foliage, causing large holes and ragged edges. To manage imported cabbageworm, handpick and remove any caterpillars found on the plant. Spray the plant with Bacillus thuringiensis (Bt).
By practicing good sanitation, crop rotation and using natural remedies, you can minimize the occurrence and damage of diseases and pests in Draba asprella Greene var. stelligera O.E. Schulz.
