Overview
Machaeranthera phyllocephala (DC.) Shinners var. megacephala (Nash) Shinners, commonly known as the Bighead Aster, is a perennial flowering plant primarily found in the Western United States. It is a member of the Asteraceae family and is known for its vibrant purple-blue flowers.
Origin and Distribution
The Bighead Aster is native to the United States and is primarily found in the Western region, including Arizona, California, Colorado, Idaho, Montana, Nevada, Oregon, Utah, and Wyoming. It is also found in the provinces of Alberta and British Columbia in Canada.
Common Names
The Bighead Aster is commonly known as the Bighead Machaeranthera, Purple Aster, and Mountain Aster.
Appearance
The Bighead Aster has an average height of around 1 to 3 feet, with a spread of up to 2 feet. It has a woody base and numerous stems with glandular hairs. The leaves are linear to oblong-lanceolate and approximately 1-2 inches long with entire margins. The flowers are found in clusters on the stem, with each having 20-45 purple-blue petals and a yellow center. The Bighead Aster blooms from May to September.
Uses
The Bighead Aster has no known significant use in traditional medicine.
However, it is a popular choice for landscaping and is suitable for rock gardens, borders, and container plantings. It thrives in full sun and well-drained soil with low to moderate water. It is resistant to drought and can tolerate cold temperatures.
Light Requirements
The Machaeranthera phyllocephala (DC.) Shinners var. megacephala (Nash) Shinners plant typically requires full sun for optimal growth. While it can tolerate partial shade, it will thrive in areas with at least six hours of direct sunlight per day.
Temperature Requirements
The plant typically grows in the USDA hardiness zones 4-9, which has an average minimum temperature range of -34.4°C (-30°F) to -6.7°C (20°F). While it can survive in temperatures as low as -15°C (5°F), it prefers temperatures between 15°C (59°F) and 30°C (86°F). The plant can easily tolerate high temperatures as it is drought-resistant and can grow in arid regions.
Soil Requirements
The Machaeranthera phyllocephala (DC.) Shinners var. megacephala (Nash) Shinners plant grows best in well-draining soils with a pH range of 5-8.5. The plant can grow in various soil types such as sandy, loamy or rocky soil. It prefers soil with low to moderate moisture content, which is why it is adapted to dry regions. The plant can also tolerate nutrient-poor soil, making it a resilient plant species.
Cultivation methods
When it comes to cultivating Machaeranthera phyllocephala var. megacephala, it's important to keep in mind that this plant thrives in a well-drained soil with full sun exposure. The best time to plant this plant is in the spring season, around April or May.Watering needs
Water this plant regularly, especially during the growing season. Ensure the soil is moist but not waterlogged, as standing water can lead to root rot. During the winter dormant period, reduce the frequency of watering, and only water when the soil starts to dry out.Fertilization
Machaeranthera phyllocephala var. megacephala requires minimal fertilization. Use a balanced fertilizer with a 10-10-10 ratio every two to three weeks during the growing season. However, avoid overfertilization as it may lead to excessive vegetative growth at the expense of flowers.Pruning
Pruning is not required for this plant, but it can be beneficial if done correctly. Deadheading spent blooms can encourage the plant to produce more flowers. Also, occasional pruning of the plant can help maintain its shape and size. The best time to prune is in late winter or early spring before new growth starts.Propagation Methods for Machaeranthera phyllocephala (DC.) Shinners var. megacephala (Nash) Shinners
Machaeranthera phyllocephala (DC.) Shinners var. megacephala (Nash) Shinners, commonly referred to as the Bighead lettuce, is a herbaceous, annual plant belonging to the Asteraceae family. The plant is native to North America and has become a popular addition to gardens due to its beautiful purple flowers and easy maintenance. Propagating Machaeranthera phyllocephala can be done using various methods, including seed and cutting propagation.
Seed Propagation
Seed propagation is one of the most commonly used methods to propagate Machaeranthera phyllocephala. The seeds can be sown either indoors or directly into the soil during early spring after the last frost. To start indoors, the seeds should be sown in individual pots or seed trays and kept moist with regular watering. The seeds should be covered with a thin layer of soil and then placed in a warm and sunny location, where they will germinate within one to three weeks.
After the seedlings have a few leaves, they can be transplanted outdoors. The seedlings should be planted in well-draining soil, and the soil should be kept moist to promote healthy growth. The plants will bloom within a few months, and the seeds produced can be collected for future propagation.
Cutting Propagation
Another method of propagating Machaeranthera phyllocephala is through cutting propagation. This method involves taking cuttings from the plant and rooting them in soil or water. Cuttings should be taken from healthy plants, using a sharp and sterile pruning tool. Cuttings should be around 4-6 inches long with several leaves.
The base of each cutting should be then dipped in rooting hormone powder to promote root formation. Once dipped in the solution, the cutting should be implanted into a container filled with moist soil. Alternatively, the cutting can be rooted in water until roots are visible, and then planted in soil.
During the rooting process, the cutting will require warm temperatures and moist soil to promote root formation. After the cutting has developed a strong root system, it can be transplanted outside and grown as any other adult Machaeranthera phyllocephala plant.
Disease Management
Machaeranthera phyllocephala (DC.) Shinners var. megacephala (Nash) Shinners is susceptible to various diseases that can significantly reduce its vigor and yield. Here are the common diseases that affect the plant and how to manage them.
Leaf Spots
Leaf spots are caused by fungal pathogens, including Cercospora and Septoria species. The disease is characterized by the appearance of small, round, brown, or black spots on the leaves. In severe cases, the leaves turn yellow and fall off prematurely, reducing the plant's ability to photosynthesize. To manage the disease, remove and destroy all infected plant debris and avoid planting new Machaeranthera phyllocephala in the same area for at least three years.
Anthracnose
Anthracnose is a fungal disease that causes wilting, yellowing, and death of the plant's shoots and leaves. The disease is characterized by the appearance of small, sunken, and dark-colored lesions on the stems and leaves. To manage the disease, avoid planting the plant in poorly drained soils, remove and destroy all infected plant debris, and use fungicides as a last resort.
Root Rots
Root rots are caused by soil-borne pathogens, including Pythium and Phytophthora species. The disease affects the plant's roots, reducing its ability to absorb water and nutrients from the soil. Symptoms of the disease include wilting, yellowing, and stunting of the plant. To manage the disease, plant the plant in well-drained soils and avoid overwatering. Use fungicides as a last resort.
Pest Management
In addition to diseases, Machaeranthera phyllocephala (DC.) Shinners var. megacephala (Nash) Shinners is susceptible to various pests that can cause significant damage to the plant. Here are the common pests that affect the plant and how to manage them.
Aphids
Aphids are sucking insects that can cause significant damage to the plant by feeding on its sap. The pests are characterized by their small size and the presence of sticky honeydew on the leaves. To manage the pests, use insecticidal soaps, neem oil, or other contact insecticides. Encourage the presence of natural enemies, such as ladybugs, lacewings, and parasitic wasps.
Caterpillars
Caterpillars are the larvae of moths and butterflies that can cause significant damage to the plant by feeding on its leaves and stems. The pests are characterized by their cylindrical body, segmented legs, and chewing mouthparts. To manage the pests, remove and destroy all infected plant debris, use Bacillus thuringiensis (BT) and other biological insecticides, and encourage the presence of natural enemies, such as birds and parasitic wasps.
Spider Mites
Spider mites are small, spider-like pests that can cause significant damage to the plant by sucking its sap. The pests are characterized by their fine webbing on the leaves and the presence of yellowing and stippling on the leaves. To manage the pests, use insecticidal soap, neem oil, or other miticides, and avoid over-fertilizing the plant.
