Origin
Symphyotrichum praealtum (Poir.) Nesom var. subasperum (Lindl.) Nesom is a flowering plant species that belongs to the Asteraceae family, native to North America.
Common Names
The plant is commonly known as eastern marsh-aster or tall American-aster, owing to the marshy habitats it prefers.
Appearance
Symphyotrichum praealtum (Poir.) Nesom var. subasperum (Lindl.) Nesom is a herbaceous perennial plant that can grow up to 2-3 meters tall. It has a strong, branching, and hairy stem with numerous leafy shoots that bear rough, alternate, and lance-shaped leaves measuring 10-15 centimeters long by 2-4 centimeters wide.
The flowers of Symphyotrichum praealtum (Poir.) Nesom var. subasperum (Lindl.) Nesom are usually pale violet or blue, sometimes with white or pink tinges, and come in loose panicles or clusters that are about 1-2 centimeters wide, with a diameter of 2-3 centimeters. The flowers feature several disk florets surrounded by a whorl of ray florets that resemble petals, although these are actually strap-like and toothed.
Uses
Symphyotrichum praealtum (Poir.) Nesom var. subasperum (Lindl.) Nesom has a long history of medicinal and culinary uses, owing to its diuretic, anti-inflammatory, and pain-relieving properties. Native American tribes used the plant's leaves and roots for treating wounds, respiratory ailments, and gastrointestinal issues. The plant's roots were also baked, roasted, or boiled, and used as a coffee substitute. Nowadays, the plant is mainly grown as an ornamental flower, used in gardens, and landscaping.
Light Requirements
Symphyotrichum praealtum var. subasperum typically grow best in areas that receive full to partial sun exposure. However, in hotter climates or during the peak of summer, some shade may be required to prevent leaf scorching. It is important to note that too much shade can result in leggy and weak growth.
Temperature Requirements
The ideal temperature range for the growth of Symphyotrichum praealtum var. subasperum is between 60 to 80°F (15 to 27°C). These plants are generally tolerant of a range of temperatures, but extremes in either direction can be detrimental to growth. Hot and dry conditions can cause premature wilting, while freezing temperatures can damage or kill the plant.
Soil Requirements
Symphyotrichum praealtum var. subasperum prefer well-drained soils that are rich in organic matter. The soil pH should be slightly acidic to neutral, with a range of 6.0 to 7.5 being ideal. These plants can tolerate a range of soil types, but sandy loam soils that retain moisture are preferred. It is important to avoid soils that are too heavy or dense, as they can cause root rot and other plant diseases.
Cultivation Methods
Symphyotrichum praealtum (Poir.) Nesom var. subasperum (Lindl.) Nesom, commonly known as rough-stemmed aster, is a herbaceous perennial plant that is easy to grow. It flourishes in full sun or partial shade and thrives in well-draining soil. It is suitable for growing in USDA hardiness zones 5 through 8. Propagation can be done through seed sowing or division of the rootstock, and it is best to plant out the young seedlings or divided plants in late spring. This gives the plants enough time to establish before the winter season.Watering Needs
The rough-stemmed aster plant requires regular watering, especially during extended periods of drought. The best practice is to maintain a consistent level of moisture in the soil. The soil should be moist but not waterlogged to prevent root rot. It is advisable to avoid overhead watering as this can cause leaf spots and encourage the spread of fungal diseases. Instead, it is recommended to water at the base of the plant and avoid splashing water on the leaves.Fertilization
The rough-stemmed aster plant does not require heavy fertilization. However, applying a balanced fertilizer once in the spring can promote healthy growth and blooming. It is recommended to use a slow-release fertilizer that will release nutrients gradually over an extended period. This will prevent the plant from getting an overdose of nutrients, which can lead to excessive growth of foliage at the expense of flowers.Pruning
The rough-stemmed aster plant doesn't require extensive pruning. However, deadheading faded flowers, and removing damaged and diseased foliage is necessary to maintain a neat appearance and promote healthy growth. It is best to prune in the spring when the plant is still dormant. At this time, it is easy to identify the dead or diseased parts of the plant. Additionally, removing healthy shoots at this time can encourage the production of more flowers later in the summer.Propagation of Symphyotrichum praealtum var. subasperum
Symphyotrichum praealtum var. subasperum can be propagated using several methods, including:
Seed propagation
Seeds of Symphyotrichum praealtum var. subasperum can be sown directly in the garden in the spring or fall. They can also be started indoors 6-8 weeks before the last frost date. The seeds should be sown on the surface of the soil and lightly covered with a thin layer of soil. Germination will occur in 10-20 days if the soil temperature is kept at 60-65°F (15-18°C). Once seedlings emerge, they should be thinned to a spacing of 12-18 inches (30-45 cm).
Division
Dividing established clumps of Symphyotrichum praealtum var. subasperum is an effective method of propagation. This should be done in the spring or fall when the plant is dormant. Carefully dig up the clump and divide it into smaller sections, making sure that each section has at least one healthy shoot and a good root system. Replant the sections in well-draining soil and water thoroughly.
Cuttings
Softwood cuttings taken in late spring or early summer can be used to propagate Symphyotrichum praealtum var. subasperum. Take cuttings that are 4-6 inches (10-15 cm) long and remove the lower leaves. Dip the cut ends in rooting hormone and plant in a well-draining potting mix. Keep the cuttings moist and in a warm, bright location out of direct sunlight. Rooting should occur in 4-6 weeks. Once roots have formed, transplant the cuttings to their permanent location in the garden.
Disease Management
Symphyotrichum praealtum is a relatively disease-resistant plant, but it is not entirely immune to some common diseases that can affect many aster species. Here are some of the most common diseases that can affect this plant and some tips for managing them:
1. Aster Yellows
Aster yellows is a disease-causing phytoplasma that can affect numerous plant species, including Symphyotrichum praealtum. It is spread by leafhoppers and can cause yellowing, stunting, and distorted growth in infected plants. Unfortunately, there is no cure for Aster yellows, so the best management strategy is to remove and destroy infected plants as soon as possible to prevent the spread of the disease to other plants.
2. Powdery Mildew
Powdery mildew is a common fungal disease that can affect aster plants, including Symphyotrichum praealtum. It can cause powdery white growth on leaves, stems, and flowers, leading to decreased photosynthesis and plant vigor. To manage powdery mildew, remove any infected plant parts, and keep the plant well-ventilated and low in humidity.
Pest Management
Symphyotrichum praealtum is also relatively pest-resistant, but some common pests can still cause problems for this plant. Here are some of the most common pests that can affect this plant and some tips for managing them:
1. Aphids
Aphids are sap-sucking insects that can cause damage to many plant species, including Symphyotrichum praealtum. They can be controlled by spraying the plant with insecticidal soap or neem oil or by introducing natural predators, such as ladybugs.
2. Spider Mites
Spider mites are tiny arachnids that can cause damage to Symphyotrichum praealtum by sucking the sap from the plant's leaves, causing them to turn yellow and develop a stippled appearance. They can be controlled by spraying the plant with insecticidal soap and increasing the humidity around the plant by misting it frequently.
