Empetrum rubrum Vahl var. atropurpureum (Fern. & Wieg.) R. Good
Empetrum rubrum Vahl var. atropurpureum, also known as red crowberry or black crowberry, is a small evergreen shrub that belongs to the heath family, Ericaceae. It is native to the arctic and subarctic regions of North America, Europe, and Asia, and can be found growing in Alaska, Canada, Greenland, Scandinavia, Siberia, and Northeast Asia.
Appearance
The plant has a low-lying growth habit, reaching a height of 10-40 cm. Its stems are woody and reddish-brown, and covered with small leaves that are needle-like and dark green in color. The leaves are arranged alternately along the stem and are 1-2 cm long. The flowers are small, pink or red in color, and appear in clusters in late spring or early summer. The fruit is a small, round berry that is blackish-purple in color and has a tart flavor.
Uses
The berries of Empetrum rubrum Vahl var. atropurpureum have been traditionally used by indigenous peoples as a food source, often eaten fresh or cooked in soups or stews. The berries are high in vitamin C, antioxidants, and flavonoids, which can help boost the immune system and protect the body against cellular damage. They are also sometimes used to make jams and pies, or fermented to make wine. Additionally, the plant has some medicinal uses, such as treating digestive issues and infections, and has been studied for its potential anti-inflammatory and anticancer properties.
The plant's low-lying growth habit, hardiness, and ability to tolerate poor soil conditions make it a good choice for landscaping and erosion control in cold climates. It is also sometimes used for ornamental purposes, such as in rock gardens or as a ground cover.
Light Requirements
Empetrum rubrum Vahl var. atropurpureum is a shade-tolerant plant that can grow well in partial shade to full sun. However, it thrives better in partial shade where it is protected from intense sunlight. When exposed to direct sunlight, the plant's leaves may turn yellow and dry out due to excessive transpiration. Therefore, it is recommended to plant Empetrum rubrum Vahl var. atropurpureum in an area with filtered light to provide adequate shade.
Temperature Requirements
Empetrum rubrum Vahl var. atropurpureum can tolerate cold temperatures with ease. It can grow in temperatures as low as -40°C (-40°F) during the winter months. However, during the summer months, the plant requires moderate temperatures ranging from 15°C to 22°C (60°F to 72°F). Temperatures above 27°C (80°F) can cause heat stress to the plant, leading to desiccation and eventual death.
Soil Requirements
Empetrum rubrum Vahl var. atropurpureum is native to acidic soils and can grow well in soils with a pH ranging from 4 to 6.5. It prefers well-drained soils that are rich in organic matter. The plant can tolerate sandy and loamy soils but does not grow well in compacted soils. It is also important to note that the plant is sensitive to soil salinity and may experience stunted growth or even die when exposed to high levels of soil salt.
Cultivation methods for Empetrum rubrum Vahl var. atropurpureum
Empetrum rubrum Vahl var. atropurpureum is a hardy plant that can be easily grown in many soil types. It prefers moist, acidic soil and grows well in both full sun and partial shade. This plant can also tolerate strong winds and cold temperatures, making it an ideal choice for gardens in colder climates.
Propagation of Empetrum rubrum Vahl var. atropurpureum can be done through stem cuttings or by seed. To propagate by stem cuttings, take a 7-10cm cutting from a healthy plant and place it in well-draining soil. Keep the soil moist until the cutting has established roots. If propagating by seed, sow the seeds in a moist, acidic soil mix and keep it well watered.
Watering needs for Empetrum rubrum Vahl var. atropurpureum
Empetrum rubrum Vahl var. atropurpureum is a drought-tolerant plant and can survive on minimal watering. However, regular watering can help the plant grow faster and increase the yield of produce. It is recommended to water the plant once or twice a week, depending on the climate and soil conditions. Ensure that the soil is well-draining to avoid waterlogging, which can cause root rot.
Fertilization of Empetrum rubrum Vahl var. atropurpureum
Empetrum rubrum Vahl var. atropurpureum does not require heavy fertilization. A light application of general-purpose fertilizer once in the growing season is sufficient. Over-fertilization can lead to excessive vegetative growth and poor fruit quality. Ensure that the soil is well-draining to avoid fertilizer burn.
Pruning of Empetrum rubrum Vahl var. atropurpureum
Empetrum rubrum Vahl var. atropurpureum does not require frequent pruning. However, removing dead or diseased wood can improve the plant's health. It is also recommended to prune off the flowers after they fade to encourage more fruit production. Avoid heavy pruning as this can reduce fruit yields.
Propagation Methods for Empetrum rubrum Vahl var. atropurpureum
Empetrum rubrum Vahl var. atropurpureum, commonly known as red crowberry, can be propagated through various methods including seed propagation, cuttings, and division.
Seed Propagation
Red crowberry can be propagated through seeds. The best time to plant the seeds is in the spring or fall. The seeds should be planted in a well-draining soil and kept moist until germination, which can take three to four weeks. Once the seedlings have grown, they can be transplanted to a permanent location.
Cuttings
Another method of propagation for red crowberry is through cuttings. Semi-hardwood cuttings should be taken in the summer or early fall. The cuttings should be treated with a rooting hormone and planted in well-draining soil. The soil should be kept moist, and the cuttings should be kept in a shaded area until they root, which can take up to six weeks.
Division
Red crowberry can also be propagated by division. This method is best done in the spring when the plant is actively growing and has not yet started to produce new shoots. The plant should be carefully dug up, and the rootball should be divided into smaller sections. Each section should have a healthy shoot and root system. The divided sections can then be replanted in well-draining soil.
Disease and Pest Management for Empetrum rubrum Vahl var. atropurpureum
Empetrum rubrum Vahl var. atropurpureum is a hardy evergreen shrub that is relatively resistant to pests and diseases. However, like any plant, it is still vulnerable to certain pests and diseases that can cause damage or reduce the health and vigor of the plant.
Common Diseases
The most common diseases that may affect Empetrum rubrum Vahl var. atropurpureum include:
- Leaf spots: Leaf spots are caused by fungal pathogens and can appear as yellow or brown spots on leaves. Fungicides can be applied to control leaf spots.
- Rust: Rust is caused by fungal pathogens and appears as orange or brown pustules on leaves. Rust can be managed by removing affected leaves and applying fungicides.
- Dieback: Dieback is typically caused by fungal pathogens and can cause the shrub to die back from the tips of the branches. Pruning affected branches and applying fungicides can help manage dieback.
Common Pests
Empetrum rubrum Vahl var. atropurpureum is relatively resistant to pests, but some pests that may affect the plant include:
- Aphids: Aphids are small insects that suck sap from the plant and can cause distortion and yellowing of leaves. Insecticidal soap can be used to control aphids.
- Spider mites: Spider mites are tiny pests that can cause yellowing and stippling of leaves. They can be controlled with insecticidal soap or neem oil.
- Caterpillars: Caterpillars can defoliate the plant and can be controlled with insecticides or by handpicking and removing the caterpillars.
Proper cultural practices, such as adequate water and nutrient management, can also help prevent and manage diseases and pests in Empetrum rubrum Vahl var. atropurpureum.
