Plant Description
Draba streptocarpa Gray var. tonsa (Woot. & Standl.) O.E. Schulz, commonly known as the shiny draba, is a small herbaceous plant from the Brassicaceae family. It typically grows to a height of 1-6 cm (0.4-2.4 inches), with a spreading mat-forming habit and basal rosette of leaves. The leaves are small, linear to oblong, and arranged in a basal rosette. The plant produces small white flowers that cluster together and bloom from April to August.
Origin and Distribution
Draba streptocarpa Gray var. tonsa is native to North America, specifically found in the Rocky Mountains and Great Basin regions. It grows in alpine and subalpine habitats, often on rocky slopes and talus.
Common Names
The plant is commonly known as the shiny draba due to the glossy appearance of its leaves. Other common names include mountain whitlow-grass and subalpine draba.
Uses
Draba streptocarpa Gray var. tonsa is not typically used for medicinal purposes or as food. However, it is sometimes used by horticulturists as a rock garden or alpine plant, due to its low-growing habit and ornamental flowers. Additionally, the plant's small size and ability to colonize open, rocky areas make it a valuable component in alpine restoration projects.
Light Requirements
The Draba streptocarpa Gray var. tonsa (Woot. & Standl.) O.E. Schulz requires full sun to thrive. Adequate sunlight promotes photosynthesis and enables the plant to produce food and grow. The plant should receive at least six hours of direct sunlight every day, and preferentially up to twelve hours of sunlight.
Temperature Requirements
The plant grows well within a specific temperature range. It thrives in cool-temperature regions with a temperature range of 10?–18? (50?–64?). The plant can survive in areas with temperatures ranging between -23? to 40? (-10?to 104?), but the ideal temperature is 14? - 16?. Temperatures above 18? (64?) can lead to the plant's early bolting, which can impact flowering.
Soil Requirements
Draba streptocarpa Gray var. tonsa (Woot. & Standl.) O.E. Schulz prefers well-drained soil with a pH level of 6 to 7. Also, the soil should be moist but well-aerated. One can mix some organic matter into the soil, such as well-rotted manure or compost before planting to improve the soil's moisture retention capacity. Furthermore, avoiding waterlogging is crucial because the plant does not grow well in soils with standing water.
Cultivation
Draba streptocarpa Gray var. tonsa (Woot. & Standl.) O.E. Schulz is a subshrub plant that grows well in full sun or light shade. It thrives best in well-drained soils, such as sandy or loamy soils, but it can tolerate some clay.
The plant does not require much maintenance and can grow in high altitudes and low rainfall regions.
Watering Needs
Regarding watering, it's crucial not to overwater the plant as it can result in root rot. The plant can survive in drought conditions for some time. It is recommendable to let the soil dry out between watering intervals.
Fertilization
Draba streptocarpa Gray var. tonsa (Woot. & Standl.) O.E. Schulz requires minimal fertilization. However, applying a light amount of nutrients during the growing season (spring) can help boost growth. A balanced fertilizer formulation such as 10-10-10 can suffice.
Pruning
The plant requires little pruning as it maintains its shape well. However, you may prune when necessary to remove any damaged or dead stems or branches. Pruning facilitates better air circulation through the plant's foliage and promotes healthy plant growth.
Propagation Methods for Draba streptocarpa Gray var. tonsa (Woot. & Standl.) O.E. Schulz
Draba streptocarpa Gray var. tonsa (Woot. & Standl.) O.E. Schulz, commonly known as the Tonopah draba, is a perennial herbaceous plant native to North America. The plant typically grows up to a foot tall with small, white flowers that bloom in the spring and summer. The plant propagates through both sexual and asexual means.
Propagation by Seed
The primary method of propagating Draba streptocarpa is through seed. The seeds are typically collected after the plant has finished blooming in the late summer and early fall. The seeds can be sown immediately or stored in a cool, dry location until the next growing season. Prior to planting, the seeds should be stratified to break dormancy. This can be done by placing the seeds in a moist medium, such as sand or vermiculite, in a cool location for several weeks or months. Once stratified, the seeds can be sown in a well-draining soil mix and kept moist until germination occurs.
Propagation by Division
Draba streptocarpa can also be propagated through division. This method involves separating the plant into smaller sections and replanting them in a new location. Division is typically done in the early spring or late fall when the plant is not actively growing. To propagate through division, carefully dig up the plant and use a sharp knife or garden spade to separate the root ball into smaller sections. Replant the sections in a well-draining soil mix and keep moist until new growth appears.
Propagation by Cuttings
Propagation by cuttings is possible for Draba streptocarpa but is less reliable than seed propagation or division. Stem cuttings can be taken during the growing season and planted in a well-draining soil mix. However, the success rate for this method is low and may require specialized growing conditions such as a high humidity environment or rooting hormone treatment.
Disease Management
Draba streptocarpa Gray var. tonsa (Woot. & Standl.) O.E. Schulz is a hardy plant that is susceptible to certain diseases, especially in moist conditions. Here are some of the common diseases that might affect the plant:
- Clubroot: It is caused by a fungus called Plasmodiophora brassicae, which causes the roots of the plant to swell and become deformed. To manage the disease, it is recommended to grow the plant in well-draining soil and avoid planting in areas with a history of clubroot.
- Blackleg: It is caused by the bacterium Xanthomonas campestris, which affects the leaves and stems of the plant. To manage the disease, it is essential to plant disease-free seeds and avoid overcrowding, as it can promote the spread of the bacteria.
- Powdery Mildew: It is caused by the fungus Erysiphe cichoracearum, which causes a white powdery coating on the leaves. To manage the disease, it is recommended to plant the Draba streptocarpa Gray var. tonsa (Woot. & Standl.) O.E. Schulz in an area with good air circulation and avoid overhead watering.
Pest Management
Draba streptocarpa Gray var. tonsa (Woot. & Standl.) O.E. Schulz can also be affected by certain pests. Here are some of the common pests that might affect the plant:
- Aphids: These are small insects that suck the sap from the leaves and stems of the plant. To manage the pest, it is recommended to spray insecticidal soap or neem oil on the plant's leaves.
- Slugs and Snails: These pests feed on the foliage and can damage the plant severely. To manage the pest, it is recommended to keep the plant's surrounding area clean and free of debris that can provide shelter to the pests. Using copper barriers or beer traps can also prove effective.
- Cabbage Worms: These are the larvae of the cabbage butterfly and can feed on the plant's leaves. To manage the pest, it is recommended to use row covers or spray the plant's leaves with Bacillus thuringiensis, a natural bacterial insecticide.
By following these disease and pest management techniques, you can keep your Draba streptocarpa Gray var. tonsa (Woot. & Standl.) O.E. Schulz healthy and thriving.
