Overview
Aster occidentalis (Nutt.) Torr. & Gray var. intermedius Gray, commonly known as the Rocky Mountain Aster or Western Aster, is a species of perennial herbaceous plant in the family Asteraceae. This plant is native to North America.
Appearance
The Rocky Mountain Aster is a tall, upright herbaceous perennial that can grow up to 4 feet in height. The plant has numerous stems that grow upward from a central rosette. The leaves are oblong-lanceolate, slightly toothed, and up to 4 inches long, with a rough texture. The flowers are daisy-like, with lavender-blue petals and yellow centers, and bloom in late summer and early fall.
Uses
The Rocky Mountain Aster, like other species in the Asteraceae family, has several traditional medicinal uses, including as a remedy for headaches, pain, and fever. The plant has also been used to make a tea that is said to have sedative properties. The plant is also grown as an ornamental for its attractive blooms and is often used in wildflower gardens or naturalized landscapes.
Distribution and Habitat
The Rocky Mountain Aster is native to the western region of North America, where it is found in a variety of habitats, including meadows, grasslands, and dry slopes. It can be found at elevations ranging from 4,000 to 11,000 feet above sea level.
Cultivation
The Rocky Mountain Aster can be propagated from seed or by division. It prefers well-draining soil and partial to full sun. The plant requires moderate watering and can tolerate drought conditions once established. It is generally pest-resistant and easy to grow, making it an excellent choice for naturalistic gardens or other landscaping projects.
Light Requirements
Aster occidentalis var. intermedius prefers to grow in full to partial sunlight. It needs at least 6 hours of sunlight to thrive. It can also grow in shaded areas but may not produce as many flowers as the plants growing in full sunlight.
Temperature Requirements
The plant can tolerate cold temperatures, but it prefers warm temperatures ranging from 60°F to 75°F. The plant can survive a temperature drop to 20°F but may not survive if the temperature drops below that. Asters grow best when the temperature and humidity are moderate.
Soil Requirements
Aster occidentalis var. intermedius likes well-drained soil that is rich in organic matter. The soil pH should be between 5.5 and 7.5. Asters do not like waterlogged soil or soil with poor drainage. Adding compost to the soil can improve its fertility and drainage. The plant is drought-tolerant, but regular watering can help the plant grow faster and produce more flowers.
Cultivation Methods
Aster occidentalis var. intermedius can be grown in full sun or partial shade. It prefers well-draining soil that is rich in organic matter. This plant tolerates a range of soil types, including clay soils, but it does not tolerate waterlogged soils. Aster occidentalis var. intermedius can be grown from seed or propagated by division in the fall.
Watering needs
Aster occidentalis var. intermedius requires moderate watering. It tolerates short periods of drought but does not tolerate overly wet soil. The plant should be watered when the soil feels dry to the touch.
Fertilization
Aster occidentalis var. intermedius benefits from fertilization, especially if grown in nutrient-poor soil. A balanced fertilizer, such as a 10-10-10, can be applied in the spring. The fertilizer should be applied to the soil around the plant according to the package instructions. Over-fertilization can lead to lush foliage and fewer flowers.
Pruning
Aster occidentalis var. intermedius benefits from pruning in the fall or early spring. Dead or damaged stems can be removed as can any diseased or insect-infested stems. Pinching back the tips of the stems can encourage bushier growth. Cutting back the plant by one-third can also stimulate new growth and promote more abundant flowering.
Propagation of Aster occidentalis (Nutt.) Torr. & Gray var. intermedius Gray
Aster occidentalis (Nutt.) Torr. & Gray var. intermedius Gray, commonly known as the western aster, is a perennial herb native to North America. It is a hardy plant that is easy to propagate.
Propagation by seeds
Propagation by seeds is the most common method for Aster occidentalis var. intermedius. The seeds should be planted in early spring in fertile, well-drained soil. The seeds must be scattered thinly and lightly covered with soil. Germination occurs in two to three weeks, and the seedlings should be thinned to 18-24 inches apart after they are established.
Propagation by division
Dividing existing plants is another propagation method for Aster occidentalis var. intermedius. Divide mature plants during spring shortly after new growth begins. The clump must be dug up carefully and separated into smaller clumps using a knife or spade. Each new clump should have at least one shoot and a portion of the root system. Replant the clumps immediately in well-drain soil with adequate moisture.
Cuttings
Aster occidentalis var. intermedius can also be propagated through stem cuttings. Choose healthy, mature stems with a length of at least 3 inches. Cut below the node and remove the lower leaves. Dip the cuttings in hormone rooting powder before planting in well-drained soil. Cover the pot with a clear plastic bag or propagator to maintain humidity and place them in bright, indirect sunlight. Once rooted (typically in around 4-6 weeks), the cuttings can be transplanted into larger pots.
Propagation of Aster occidentalis var. intermedius is simple and straightforward. With proper care, you can have many plants to enjoy for years to come.
Pest Management
One of the most common pests that affect the Aster occidentalis is the aphids. These feeding insects tend to cause curling, yellowing or browning of leaves, stunted growth and may even spread viral diseases. Fortunately, these insects can be managed by using insecticidal soap or horticultural oils. Some other common pests include spider mites, thrips, and leafhoppers. These pests can also be managed by using horticultural oils, insecticidal soap, or neem oil.
Disease Management
The Aster occidentalis is also prone to some common diseases that affect other plants in the Asteraceae family. Powdery mildew is a common fungal disease that causes white powdery coating on leaves and may reduce the plant's vigor. To manage this disease, apply fungicides, prune infected leaves and increase air circulation around the plant. Downy mildew is another fungal disease that causes yellowing or browning of foliage. Pruning affected leaves and managing the plant's stress factors such as overwatering or poor soil drainage can help manage this disease effectively.
Aster yellows is a major disease that is caused by a phytoplasma bacteria and affects various plants in the Asteraceae family. The disease causes yellowing, stunted growth and deformation of leaves, flowers, and stems. However, it is not easy to control Aster yellows effectively, so it is best to prevent it by using healthy planting material, practicing crop rotation and avoiding plant stress factors.
