Overview
Draba corrugata S. Wats. var. saxosa (A. Davids.) Munz & Johnston is a small, evergreen plant that belongs to the Brassicaceae family. It is a subalpine species that is widely distributed in the western region of North America, ranging from California to British Columbia.
Common Names
Commonly known as the Rocky Mountain draba or Saxifrage-leaf draba, this plant is also referred to as the corrugate draba or Davids' draba.
Appearance
The plant generally grows in a compact cushion form and can reach up to 2.5 cm in height. The leaves of Draba corrugata S. Wats. var. saxosa are deeply corrugated and toothed at the margin, with a narrow ciliate base. The basal leaves measure 4-15 mm long and 1-2 mm wide, while the stem leaves are reduced and widely spaced. The flowers are typically white to cream-colored and grow in dense clusters at the end of the leafy stems. The fruit is a small, flat silique, measuring 3-6 mm long.
Uses
While Draba corrugata S. Wats. var. saxosa is not commonly cultivated in gardens, it has been used for medicinal purposes by indigenous people. The plants are high in vitamin C and have been traditionally used as an herbal remedy for colds and sore throats. Additionally, the species grows well in rock gardens, alpine troughs, or among stones, making it an ideal option for gardeners looking to create naturalistic, low-maintenance landscapes.
Light Requirements
Draba corrugata S. Wats. var. saxosa (A. Davids.) Munz & Johnston thrives in full sun, requiring at least 6 hours of direct sunlight per day. However, it can tolerate partial shade for a few hours each day. It is essential to provide adequate light levels for the plant's optimum growth and development.
Temperature Requirements
The plant prefers cool temperatures ranging from 45 to 60 degrees Fahrenheit. It grows well in USDA hardiness zones 4 to 7, which have a cool climate, but it may struggle in warmer climates. The plant requires a cool environment to produce an abundance of flowers and maintain overall health.
Soil Requirements
Draba corrugata S. Wats. var. saxosa (A. Davids.) Munz & Johnston prefers well-draining, slightly acidic soils with a pH range of 6.0 to 7.0. The soil type can vary from sandy loam to clay loam, but it should have good drainage to prevent waterlogging. The plant can tolerate nutrient-poor soils, but it prefers a moderately fertile soil. Adding organic matter, such as compost or well-rotted manure, can help improve the soil's fertility.
Cultivation Methods
Draba corrugata S. Wats. var. saxosa (A. Davids.) Munz & Johnston, commonly known as rolling rockcress or corrugated draba, is a cold-hardy perennial plant that is native to rocky areas of the western United States.
This plant grows best when cultivated in well-draining soil that is sandy, loamy, or gravelly, with a pH level of 5.6 to 7.5. It prefers full sun to partial shade and requires a cool climate with moderate moisture and high humidity.
To cultivate this plant, ensure that the soil is well-draining and has a pH level between 5.6 and 7.5. Plant the seeds in early spring or fall, placing them 1/8 inch deep and 1 inch apart. Water the seeds gently, ensuring that the soil stays moist but not saturated. Germination usually occurs within 2-3 weeks, and the plants will grow to full maturity within 2-3 years.
Watering Needs
Draba corrugata requires moderate but consistent watering. The plant prefers a well-draining soil that is kept moist, but not waterlogged. Water the plant regularly during the growing season, ensuring that the soil stays moist but not saturated.
During dry spells, increase the frequency of watering to prevent the soil from drying out. Avoid overhead watering, as this can lead to mold and fungus growth and damage the plant's delicate foliage.
Fertilization
Draba corrugata does not require heavy fertilization. In fact, too much fertilizer can harm the plant and even kill it.
If the soil quality is poor, add compost or organic fertilizers during the planting process. After the plant has become established, fertilize it once a year in early spring with a slow-release, balanced fertilizer. Apply the fertilizer according to the manufacturer's instructions.
Pruning
Draba corrugata does not require regular pruning. However, deadheading spent blooms can encourage the plant to produce more flowers. Remove dead and damaged foliage as needed to keep the plant looking neat and healthy.
Prune the plant in early spring to remove any dead or damaged branches. Cut the branches back to healthy wood, being careful not to damage the main stem. Prune sparingly to avoid damaging the plant's delicate structure.
Propagation of Draba corrugata S. Wats. var. saxosa
Draba corrugata S. Wats. var. saxosa, commonly known as the San Gabriel Mountain draba, is a small perennial herb and member of the mustard family (Brassicaceae). Propagation of this plant is typically done using seeds and vegetative methods.
Propagation by seeds
The San Gabriel Mountain draba produces small seeds that are dispersed by wind. When propagating by seed, it is important to collect the seeds when they are mature, which is typically in mid-summer.
After collecting the seeds, it is important to clean them and sow them immediately in a suitable growing medium. The seeds require light for germination, so they should be sown on the surface of the growing medium and kept moist. Germination should occur within two to three weeks.
Propagation by vegetative methods
Propagation of the San Gabriel Mountain draba can also be done by vegetative methods, such as division and cuttings.
Division involves carefully separating the plant into smaller sections and replanting them. This method is typically done in the spring or fall.
Cuttings involve taking a stem cutting from the plant and rooting it in a suitable growing medium. This method is typically done in the spring or summer.
Overall, propagating Draba corrugata S. Wats. var. saxosa is relatively easy and can be done using a variety of methods.
Disease and Pest Management for Draba corrugata S. Wats. var. saxosa (A. Davids.) Munz & Johnston
Draba corrugata S. Wats. var. saxosa (A. Davids.) Munz & Johnston, commonly known as Stonecress or Rock Draba, is a low-growing alpine plant that thrives in dry, rocky soils. While it is generally a hardy plant, it may be prone to various diseases and pest problems, especially when grown in less-than-ideal conditions. It is important to be able to recognize these potential problems and take appropriate measures to manage them.
Common Diseases
One common disease that may affect Stonecress plants is powdery mildew, which appears as a white powdery substance on leaves and stems. This disease can be prevented by ensuring adequate air circulation around the plant and avoiding overhead watering. If powdery mildew does appear, it can be treated with a fungicide labeled for use on this specific plant.
Root rot may also be a problem for Draba corrugata var. saxosa, especially if the soil is consistently damp. To prevent this disease, be sure to plant in well-drained soil and avoid overwatering. If root rot does develop, it may be necessary to remove affected plants and treat the remaining soil with a fungicide.
Common Pests
Aphids can be a problem for Stonecress plants, especially if they are grown in shaded or crowded conditions. These small insects feed on plant sap and can cause leaf distortion and yellowing. To manage an aphid infestation, try using insecticidal soap or neem oil. Introducing natural predators, such as ladybugs or lacewings, can also be effective.
Snails and slugs may also be a problem for Stonecress plants, particularly in areas with high humidity. These pests can be controlled with baits or by handpicking them off the plant. Be sure to remove any hiding places for snails and slugs, such as piles of leaves or debris.
Overall, the key to managing disease and pest problems in Draba corrugata var. saxosa is to prevent them before they occur. By providing optimal growing conditions and monitoring the health of your plants, you can reduce the likelihood of problems and ensure a healthy, vibrant garden.
