Origin
Streptanthus glandulosus Hook. var. albidus (Greene) Jepson, commonly known as white-veined jewelflower, is a herbaceous plant that is native to California, specifically in the North Coast, Klamath Ranges, and Northern Inner Coast Ranges.
Common Names
The white-veined jewelflower has different common names such as harlequin rock cress, glandular jewelflower, and Sierra jewelflower.
Uses
The plant is commonly used for ornamental purposes due to its unique and delicate appearance that can add beauty to any garden or landscape. Additionally, some Native American tribes have utilized the plant for medicinal purposes, such as a poultice for skin wounds and as a treatment for stomachaches.
General Appearance
The white-veined jewelflower is a biennial or perennial plant that grows up to 60 centimeters tall. The plant bears cauline leaves that are lanceolate, toothed, and reach up to 10 centimeters long. Its showy flowers are white or lavender and are clustered in elongated, spring-like racemes. The flowers are characterized by their four petals and six yellow stamens, similar to those of a classic crucifer. What sets apart the white-veined jewelflower is its unique and striking feature, which is the white veins on its lavender sepals, giving it a veined or asterisk-like appearance.
Light and Temperature Requirements
Streptanthus glandulosus var. albidus can grow in full sun to partial shade. It is generally found in dry or semi-dry areas like hillsides, canyon walls, and chaparral. The plant can tolerate temperatures ranging from 15°C to 30°C, but it grows best in temperatures between 20°C to 25°C.
Soil Requirements
The plant prefers well-draining soils with good aeration and a pH of 6.5 to 7.5. It can grow in a variety of soils, including sandy, loamy, or rocky soils. However, it thrives in sandy loam or clay soils that retain moisture instead of running off. The plant is also tolerant of infertile soils but benefits from occasional nitrogen fertilization.
Water Requirements
Streptanthus glandulosus var. albidus is adapted to arid environments and requires little water once established. It can survive on natural rainfall, but occasionally watering the plant during drought periods can promote growth. Overwatering the plant can lead to root rot or other fungal diseases, so it's important not to water the plant excessively.
Other Growing Conditions
The plant can tolerate mild frost but may freeze in severe winter conditions. It has a deep taproot and prefers a larger pot if grown in containers. Streptanthus glandulosus var. albidus is a self-sowing plant, and its seeds can spread over long distances, making it a resilient species that can adapt to different environments.
Cultivation Methods
Streptanthus glandulosus Hook. var. albidus (Greene) Jepson is a native to the dry slopes and cliffs of California. It typically grows in rocky soils in the wild, so it is best to replicate these conditions when cultivating. Therefore, it is recommended to plant it in well-draining soil, preferably rocky, and in an area with plenty of sunshine. It also thrives in areas with moderate to low humidity levels.
When starting from seeds, plant them in early autumn before the first frost. The seeds typically take two to four weeks to germinate, and the seedlings can be transplanted to their permanent location once they reach about two inches in height.
Watering Needs
Although Streptanthus glandulosus Hook. var. albidus (Greene) Jepson is drought-resistant, it still needs to be watered regularly. However, care should be taken not to overwater as this can lead to root rot. It is recommended to water the plant once a week, ensuring that the soil is moist to a depth of about six inches.
Fertilization
Being a native plant, Streptanthus glandulosus Hook. var. albidus (Greene) Jepson does not require regular fertilization. However, in cases where the soil is nutrient-poor or when cultivating the plants in containers, a balanced fertilizer may be used during the growing season. It is recommended to use a slow-release fertilizer and to follow the instructions on the package for optimal results.
Pruning
Streptanthus glandulosus Hook. var. albidus (Greene) Jepson should be pruned after the blooming season has ended. The plant tends to self-seed, so it is advisable to deadhead the spent flowers before they drop their seeds to prevent uncontrolled spread. Additionally, pruning helps to promote bushier growth in the plant and maintains its shape. When pruning, use a clean, sharp pair of pruning shears and cut the stem just above the leaf nodes for optimal regrowth.
Propagation of Streptanthus glandulosus Hook. var. albidus (Greene) Jepson
Streptanthus glandulosus Hook. var. albidus (Greene) Jepson, commonly known as white-bracted jewelflower, is a native perennial herb that belongs to the Brassicaceae family. Propagation of this plant can be done through seeds and stem cuttings.
Propagation by Seeds
Propagation of Streptanthus glandulosus Hook. var. albidus (Greene) Jepson through seeds is relatively easy and straightforward. The seeds should be collected from healthy and mature plants during the fall season. The seeds should be cleaned and air-dried before storing them in a cool and dry place until spring.
In the spring, the seeds should be sown in a seed tray or directly in the ground after the last frost. The seeds should be sown at a depth of 1/8 inch and kept evenly moist. Germination usually occurs within two to three weeks, and the seedlings should be thinned to six inches apart.
Propagation by Stem Cuttings
Propagation of Streptanthus glandulosus Hook. var. albidus (Greene) Jepson through stem cuttings is another effective method. The stem cuttings should be taken from healthy and mature plants during the summer season. The cuttings should be four to six inches long and should have at least two to three nodes and several leaves.
The cuttings should be dipped in rooting hormone and planted in a seed tray filled with a well-draining potting mix. The tray should be covered with a plastic bag or kept in a propagation chamber to maintain high humidity. The cuttings should be watered regularly and kept under bright, indirect light. After four to six weeks, the cuttings should develop roots and can be transplanted to individual pots or directly in the ground.
Whether propagation is done through seeds or stem cuttings, it is important to keep the new plants well-watered and weed-free during their establishment period.
Disease Management
Streptanthus glandulosus Hook. var. albidus (Greene) Jepson, commonly known as white-bracted jewelflower, is prone to a few diseases, which can significantly affect its growth and development. The following are some of the common diseases that affect this plant and ways of managing them:
Blackleg
Blackleg is a disease caused by the bacterial pathogen, Xanthomonas campestris. It affects the plant's stems and leaves resulting in wilting, yellowing, and eventually death. To manage this disease, remove all infected plants and avoid planting jewelflowers in the same area for at least two years. You should also sterilize your pruning tools after each use.
Downy Mildew
Downy mildew is caused by the fungus, Peronospora sparsa, and is characterized by yellowing and wilting of leaves, and stunted growth. To manage this disease, ensure that the planting area has good drainage. Avoid planting in areas that remain wet or humid for long periods. You can also use fungicides to control the spread of this disease.
Pest Management
Streptanthus glandulosus Hook. var. albidus is also susceptible to pest infestations, which can compromise its growth and yield. Some of the common pests that may attack this plant are:
Aphids
Aphids are small, soft-bodied insects that suck the sap from the leaves. This leads to yellowing, wilting, and stunted growth. To manage these pests, prune infested leaves and stems, and remove any weeds around the plant. You can also introduce natural predators such as ladybugs or lacewings to your garden.
Cutworms
Cutworms are the larvae of moths and cut the stem at the base, resulting in wilting and death of the plant. To manage these pests, avoid planting young seedlings in areas with high infestation. You can also use organic insecticides such as Bacillus thuringiensis var. kurstaki (Btk) to control the spread of these pests.
By implementing these disease and pest management strategies, you can maintain healthy and productive white-bracted jewelflowers.
