Origin
Physostegia correllii (Lundell) Shinners, commonly known as Correll's obedient plant, is a native perennial herb that grows in the southeastern part of the United States. It is a member of the mint family, Lamiaceae, and is closely related to other species of the genus Physostegia.
Common Names
Correll's obedient plant, named after American botanist Donovan Stewart Correll, is also commonly known as false dragonhead, obedient plant, and lion's heart.
Uses
Correll's obedient plant has not been used extensively for medicinal purposes. However, its root has been used as a remedy for stomach ailments in traditional Native American medicine. The plant is primarily grown for its ornamental value, as it produces showy spikes of white to light, bluish-purple flowers that bloom from July through October. It is also used as a border plant and makes a beautiful addition to wildflower gardens.
General Appearance
Correll's obedient plant grows up to three feet tall and two feet wide, with green lanceolate leaves that grow up to four inches long. The plant's stems are square and hairy. Its flowers are tubular with two-lipped corollas that can grow up to two inches long. The plant's fruit is a reddish-brown, four-chambered capsule, which contains small seeds.
Light Requirements
Physostegia correllii is typically a full sun plant, meaning it requires at least six hours of direct sunlight per day for optimal growth. However, it can also tolerate partial shade. When grown in partial shade, the plant may have fewer flowers but will still grow well.
Temperature Requirements
Physostegia correllii grows best in warm temperatures, between 60° and 80°F (15.5° and 26.7°C). The plant can tolerate colder temperatures down to about 20°F (-6.7°C) and can survive light frosts. However, it is not recommended to expose the plant to extended periods of frost or freezing conditions as it can damage the plant.
Soil Requirements
Physostegia correllii grows best in well-drained soils that are neutral to slightly alkaline (pH 6.0-7.5). The plant prefers soils that are moist but not waterlogged. It can tolerate some drought conditions, but the soil should never be allowed to completely dry out.
The plant is adaptable to different soil types, but it grows best in fertile soils that are rich in organic matter. Adding compost or other organic amendments to the soil can help improve soil quality and provide the necessary nutrients for healthy growth.
Cultivation Methods
Physostegia correllii, commonly known as Correll's false dragonhead, is a hardy perennial plant that thrives in full or partial sunlight. It grows well in moist, well-draining soils and can tolerate a wide range of soil types, including clay and loam. The plant can be propagated from seeds or vegetative cuttings. When planting the seeds, it is recommended to sow them about 1/8 inch deep in the soil during the fall season. The cuttings can be planted directly into the soil after dipping them in a rooting hormone. Once established, the plant can tolerate some drought conditions, but it prefers to be watered regularly.
Watering Needs
The Physostegia correllii plant needs adequate watering to thrive. It prefers moist soils that are well-draining, so it is essential to water it once the top layer of soil dries up. The frequency of watering depends on the weather conditions, soil type, and the location of the plant. When watering, it is recommended to avoid overwatering, as this can cause root rot and other fungal diseases.
Fertilization
The Correll's false dragonhead plant does not require much fertilization. However, it can benefit from an annual application of slow-release fertilizer during the spring season to stimulate growth. It is recommended to use a well-balanced fertilizer with equal parts of nitrogen, phosphorus, and potassium.
Pruning
Pruning can help to improve the appearance and overall health of Physostegia correllii. It is recommended to prune the plant in the fall after the blooming season has ended. Cut back the stems to one-third of their initial height to promote bushy growth the following season. Deadheading spent flowers during the growing season can also encourage new blooms.
Propagation of Physostegia Correllii
Propagation of Physostegia Correllii can be done through a variety of methods, each with its own advantages and disadvantages.
Seed Propagation
One of the most common methods of propagation for Physostegia Correllii is through seeds. The seeds should be sown in the early spring, in a well-draining soil mix that is moistened to avoid drying out. Cover the seeds loosely with soil and wait for the seedlings to emerge, which typically takes around 7 to 10 days. Keep the soil moist and maintain a temperature of around 68-72°F for optimal growth. Once the seedlings have developed their second set of leaves, they can be transplanted into individual pots or into the garden bed.
Division
Another way to propagate Physostegia Correllii is through division, which can be done in the spring or early fall. Gently dig up the clump of Physostegia Correllii and separate it into smaller sections, each with its own root system. Transplant these sections into individual pots or into the garden bed, making sure to keep the soil moist for optimal growth.
Cuttings
Propagation through cuttings is also possible with Physostegia Correllii. Cut off a 4-6 inch section of the stem, making sure it has at least one node. Remove any leaves from the bottom half of the stem, and dip the cut end into a rooting hormone powder. Plant the cutting in a well-draining soil mix and keep it moist. Place a plastic bag over the top of the pot to help maintain humidity, and keep it in a warm, bright spot. Once the cutting has developed roots, it can be transplanted into an individual pot or into the garden bed.
Disease and Pest Management for Physostegia correllii (Lundell) Shinners
Although Physostegia correllii (Lundell) Shinners is generally a hardy plant, it can still fall victim to certain diseases and pests. Here are some of the most common issues and how to manage them:
Diseases
Powdery Mildew: This fungal disease is one of the most common issues for Physostegia correllii. It presents as a white, powdery substance on the leaves and flowers and can lead to the plant’s decline. Planting the plant in well-draining soil and ensuring proper air circulation can help prevent the disease. Treating the plant with a fungicide may also help alleviate symptoms.
Fungal Leaf Spots: These fungal infections can present as circular or irregularly shaped spots on the leaves. They are typically caused by overly moist conditions and can be managed by watering the plant early in the day and ensuring it is planted in well-draining soil. In severe cases, a fungicide may be necessary.
Pests
Aphids: These small, soft-bodied insects can cause damage by piercing the plant and sucking sap. They can be managed by spraying the plant with a strong stream of water or treating with insecticidal soap or neem oil.
Spider Mites: These tiny pests can cause damage to the leaves by piercing them and sucking sap. Infested leaves may appear speckled or silver in color. Spider mites can be managed by spraying the plant with water and using insecticidal soap or neem oil.
Whiteflies: These small, moth-like insects can cause damage by sucking sap and causing leaf yellowing and dropping. They can be managed by spraying the plant with a strong stream of water or treating with insecticidal soap or neem oil.
Ensuring proper care and maintenance of Physostegia correllii can go a long way in preventing and managing diseases and pests. Regularly checking the plant and promptly addressing any issues can also help keep it healthy and thriving.
