Overview
Phlox stansburyi (Torr.) Heller ssp. superba (Brand) Wherry is a flowering plant native to the western United States. It is commonly known as Superb Phlox.
Appearance
The Superb Phlox is a herbaceous perennial that grows up to 18 inches tall and 12 inches wide. It has narrow leaves that are about 2 inches long and ¼ inch wide. The flowers of the Superb Phlox are pink, purple, or lavender, and they grow in clusters at the top of long stems. They bloom from late spring to early summer and have a fragrant scent.
Origin
Superb Phlox is native to the western United States, specifically in the Great Basin region, including Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, and Wyoming.
Uses
Superb Phlox is mainly grown as an ornamental plant for its beautiful, fragrant flowers. It is an excellent choice for rock gardens or as a border plant. It is also a great choice for attracting bees and butterflies to the garden. Additionally, some Native American tribes use the roots of this plant as a traditional medicine for various ailments.
Growth Conditions of Phlox stansburyi (Torr.) Heller ssp. superba (Brand) Wherry
Light Requirements: Phlox stansburyi ssp. superba prefers full sun to partial shade and grows well in areas that receive at least 6 hours of direct sunlight per day. Inadequate light can cause stunted growth and reduced flowering.
Temperature Requirements: This plant species thrives in cool to temperate regions with average daytime temperatures ranging from 60 to 75°F. They are hardy plants that can tolerate a wide range of temperatures as long as they are not exposed to extreme heat or frost.
Soil Requirements: Phlox stansburyi ssp. superba prefers well-drained, slightly acidic soils with a pH of 5.5 to 7.0. This plant species can tolerate various soil types, including sandy, loamy, and clay soils. However, they do not tolerate waterlogged or compacted soils, which can lead to root rot and hinder growth.
Water Requirements: Phlox stansburyi ssp. superba requires moderate watering and prefers slightly moist soil. Overwatering can lead to root rot and fungal diseases, whereas underwatering can cause wilting and reduced growth. It is important to water this plant species at the soil level and avoid getting water on the leaves and flowers, which can cause damage and fungal infections.
Fertilizer Requirements: Phlox stansburyi ssp. superba does not require frequent fertilization and can survive on minimal nutrients. However, to promote optimum growth and flowering, it is recommended to apply a balanced fertilizer with an N-P-K ratio of 10-10-10 once a month during the growing season.
Propagation: This plant species can be propagated through seed or division. Seeds should be sown in early spring in a well-draining soil mix and kept moist until germination. Division can be done in the fall or early spring by separating clumps of the plant and replanting them in a new location.
Cultivation
Phlox stansburyi (Torr.) Heller ssp. superba (Brand) Wherry is a hardy plant that thrives in various soil types, such as sandy or loamy soils, with a pH range of 5.5 to 7.5. It can grow in both sunny and partially shaded areas and requires adequate air circulation to prevent the occurrence of fungal diseases, such as powdery mildew. The best time to plant this species is during the spring or fall when the temperature is mild enough for the plant to establish its root system.
Watering Needs
Phlox stansburyi (Torr.) Heller ssp. superba (Brand) Wherry requires a moderate to high amount of water to thrive. It prefers well-draining soils that do not retain water, as waterlogging can lead to root rot. The plant should receive at least one inch of water per week, either through rainfall or irrigation. However, it is important not to overwater the plant, as it can cause leaf yellowing and other symptoms of stress.
Fertilization
Phlox stansburyi (Torr.) Heller ssp. superba (Brand) Wherry does not require frequent fertilization, as it is a low-maintenance plant. However, adding a slow-release, balanced fertilizer to the soil during the spring can help promote healthy growth and flowering. Additionally, organic amendments, such as compost or aged manure, can provide essential nutrients to the soil and improve its structure.
Pruning
Phlox stansburyi (Torr.) Heller ssp. superba (Brand) Wherry does not require significant pruning, as the plant has a natural, compact growth habit. However, regular deadheading of spent blooms can encourage new growth and prolong the flowering period. Additionally, removing any damaged or diseased stems or foliage can help prevent the spread of pests and diseases.
Propagation of Phlox stansburyi (Torr.) Heller ssp. superba (Brand) Wherry
Phlox stansburyi (Torr.) Heller ssp. superba (Brand) Wherry, commonly known as Stansbury's phlox, is propagated through both sexual and asexual means.
Propagating through seeds
The plant produces small seeds, which can be sown directly into the garden bed. However, it is important to note that the seeds require stratification, a process of exposing them to moist, cold conditions to break their dormancy before sowing. This can be achieved through sowing them in the fall, so they can naturally experience winter conditions, or by keeping them in a fridge for several weeks before sowing in the spring.
Propagating through division
Phlox stansburyi can also be propagated through division, a process of separating the plant into smaller sections and replanting them. This method is best done in the early spring or fall, when the plant is dormant or just starting to grow again. Care should be taken to not damage the root system while dividing, and the new sections should be planted at the same depth as the original plant.
Propagating through cuttings
The plant can also be propagated through stem cuttings, although this is a more challenging method and not always successful. Cuttings should be taken in the early summer when the plant is actively growing, and the cuttings should be treated with a rooting hormone before being planted either in a pot or directly into the garden bed. Regular watering and misting are required until the cuttings have rooted and started to produce new growth.
Disease Management
Phlox stansburyi ssp. superba is generally a healthy plant with moderate susceptibility to some diseases.
One of the most common diseases affecting Phlox stansburyi ssp. superba is powdery mildew caused by Erysiphe cichoracearum. The disease is characterized by white powdery patches on the leaves, which may eventually yellow and die. To manage powdery mildew, it is essential to ensure proper air circulation by thinning dense canopies and maintaining proper spacing between plants. Additionally, pruning heavily infected areas is also an effective control measure. Fungicides like sulfur or neem oil may be used to control severe outbreaks of powdery mildew.
Anthrachnose caused by the fungi, Colletotrichum phlogis, also affects Phlox stansburyi ssp. superba. The disease is characterized by brown lesions that encircle the stem or leaf blade, causing the foliage to wilt and die. The disease can be controlled by the application of fungicides like copper, chlorothalonil, or mancozeb. Alternatively, resistant cultivars may be planted if the disease is severe.
Botrytis cinerea, a fungal pathogen that causes grey mold, may also affect Phlox stansburyi ssp. superba. The disease is characterized by greyish-brown fuzzy patches on the foliage and flowers of the plant. To manage this disease, the foliage should be kept dry by reducing humidity and improving air circulation. Additionally, the removal of affected plant parts and the use of fungicides can be effective in controlling the disease.
Pest Management
Phlox stansburyi ssp. superba is not prone to severe insect attacks. However, some pests may damage the foliage and flowers of the plant.
Aphids are small sap-sucking insects that may cause stunted growth and yellowing of leaves. They can be controlled by spraying the plant with insecticidal soap or neem oil.
Spider mites are tiny arachnids that live on the underside of leaves, causing stippling and bronzing of foliage. They can be controlled effectively by keeping foliage well-watered and by spraying with neem oil or insecticidal soap, which disrupts their feeding patterns, ultimately killing them.
Thrips are small, slender insects that cause flower damage by feeding on the petals. The best way to manage thrips is to monitor the plants regularly and remove infested flowers. Additionally, spraying the plant with insecticidal soap or neem oil can control the population of thrips.
Caterpillars may also chew holes in the foliage and flowers of Phlox stansburyi ssp. superba. They can be controlled by picking them off manually and spraying the plant with Bacillus thuringiensis, a naturally occurring bacterium that is toxic to caterpillars.
