Calystegia purpurata (Greene) Brummitt - Overview
Calystegia purpurata, also commonly known as purple bindweed, is a species of flowering plant that belongs to the family Convolvulaceae. It is native to the coastal regions of western North America, ranging from British Columbia to California.
Physical Appearance and Characteristics
Purple bindweed is a perennial plant that can grow up to 3 meters in length. The plant has arrowhead-shaped to triangular leaves that alternate along its vines. The leaves are usually 5-10 cm long and 2-6 cm wide. The flowers are trumpet-shaped and are about 4-7 cm long and 3-5 cm wide. The petals are fused together, forming a tube-like structure with two lobes at the tip, displaying the hues of pink, magenta, or purple. The plant fruits are egg-shaped to oval-shaped capsules ranging from 1 to 1.5 cm long and are divided from the top in two parts, containing exceptionally small seeds.
Common Names and Uses
Purple bindweed has several common names, including morning glory, Pacific false bindweed, coast range hedge bindweed, and western morning glory. The plant's roots and leaves have been traditionally used in the form of an infusion as a remedy for asthmatic coughs, wounds, and snakebites. However, it is necessary to note that Calystegia purpurata is highly toxic and can cause severe health issues if ingested. Hence, it is advisable to use the plant strictly under expert supervision.
In recent times, the plant has increasingly been appreciated in gardens and landscapes for its attractive foliage and showy flowers. The plant serves as a natural boundary for yards and also adds to the aesthetic pleasure of any garden with its glorious purple blooms.
Light Requirements
Calystegia purpurata typically grows best under full sunlight exposure. Some shading is tolerable, but too much shade can hinder the growth and flowering of the plant. For optimum growth and development, it is advisable to plant the species in an open area that receives direct sunlight for at least 6 hours per day.
Temperature Requirements
The plant thrives in a wide range of temperatures, from 10°C to 32°C. However, it is crucial to note that extremely low or high temperatures can be detrimental to its growth. The optimal growth temperature for Calystegia purpurata is between 18°C and 25°C.
Soil Requirements
The plant prefers well-draining soils that are nutrient-rich. The soil pH should be in the range of 5.5 to 6.5 for optimal growth. If the soil is too acidic or alkaline, it can lead to stunted growth and poor flowering. The plant can grow in different types of soils, including sand, loam, or clay, but optimal development is achieved in loamy soils that are rich in organic matter and nutrients. It is recommended to amend the soil with compost or other organic matter before planting to improve the soil quality and nutrient content.
Cultivation Methods
Calystegia purpurata, commonly known as California morning glory, can be easily grown in a variety of soils. However, they prefer well-draining, loamy soil enriched with organic matter. The plant thrives in full sun but can tolerate partial shade as well. It is advisable to plant the seeds in early spring.
Watering Needs
Proper watering is crucial for the growth and survival of Calystegia purpurata. The plant requires regular watering, especially during hot and dry weather conditions. It is recommended to water deeply once every week, ensuring that the water penetrates the root zone. However, too much water can lead to root rot, so it's important to avoid over-watering.
Fertilization
Calystegia purpurata is a light feeder, which means it doesn't require a lot of fertilization. You can add a layer of compost to the soil once a year or use a balanced, slow-release fertilizer in the early spring. Avoid using high-nitrogen fertilizers as this can result in excessive foliage growth with fewer flowers.
Pruning
Pruning is necessary to keep Calystegia purpurata under control as it can grow vigorously and spread quickly. You can pinch the tips of the plant to encourage it to branch out and become bushy. Pruning also helps to improve air circulation and reduce the risk of fungal diseases. It's best to prune the plant during the dormant season, i.e., in late fall or winter.
Propagation of Calystegia purpurata
Calystegia purpurata, also known as purple bindweed, is a perennial vining plant that is native to North America. It is commonly found and used in landscapes and gardens due to its attractive purple flowers and ability to cover unsightly areas. Propagation of Calystegia purpurata can be done in several ways:
Propagation by Seeds
Propagation by seeds is a relatively simple and effective method for growing new Calystegia purpurata plants. Mature seeds can be collected from the plant and stored indoors until they are ready to be planted. It is best to sow the seeds in the spring or early summer directly into the soil, as they require sunlight to germinate. The soil should be kept moist, but not waterlogged, and the seedlings should be thinned to provide adequate space for growth.
Propagation by Cuttings
Propagation by cuttings is another way to grow a new Calystegia purpurata plant. This method involves taking a cutting from the parent plant, rooting it in water or soil, and then transplanting it into a new location. Ideally, the cutting should be taken in the spring or summer when the plant is actively growing. Cuttings should be taken near the tip of a shoot, and the bottom leaves should be removed. The cutting should be placed in water or soil and kept moist until roots develop.
Propagation by Division
Propagation by division is a method that involves dividing the plant's root system into smaller sections and replanting them. This method is best done in the fall or early spring when the plant is dormant. The plant should be dug up carefully, and the roots should be divided into sections. Each section should have enough roots and shoots to sustain it, and the sections can then be replanted in a new location. Care should be taken to keep the roots moist during the process.
Disease Management
Calystegia purpurata is generally a disease-resistant plant, and it can stand up to most diseases that affect it, thereby keeping it thriving. However, some issues can occur and require specific measures to keep them away from causing catastrophic problems.
Phytophthora Root Rot: This disease is caused by a fungus-like protozoan that belongs to the Phytophthora genus. The common symptoms of this disease in Calystegia purpurata include wilting, yellowing of foliage, and an early death. Controlling the spread of Phytophthora root rot can be done through soil sterilization, improving drainage and aeration, and avoiding over-irrigation. Additionally, avoidance of planting in affected areas is recommended.
Powdery Mildew: This is a fungal infection that appears as a white powdery coating on the plant's leaves. It can lead to leaf yellowing and early defoliation. The best prevention strategy for powdery mildew is planting in well-ventilated areas as the fungus thrives under high humidity. Additionally, removing affected parts and practicing proper pruning will slow down the spread of this disease. Fungicides can also be applied, but their effectiveness may vary depending on the powdery mildew fungi prevalent in the region.
Pest Management
Calystegia purpurata can be attacked by a variety of pests that may cause defoliation, yellowing of foliage, and reduction in the overall plant growth if left untreated. Below are common pests that affect Calystegia purpurata, and how to manage them:
Spider Mites: These pests are small and often difficult to spot. They suck sap from the plant and cause yellowing of the foliage. Control measures include periodic washing foliage, increasing humidity levels, and applying a miticide insecticide if necessary.
Caterpillars: Caterpillars can defoliate Calystegia purpurata significantly. They can be controlled through handpicking of the larvae or applying a biological control agent, Bacillus thuringiensis (B.t.) if necessary.
Aphids: These insects suck sap and cause curling and yellowing of the foliage. Aphids can be controlled using insecticidal soap or neem oil. Additionally, washing foliage periodically with water and practicing companion planting can reduce infestations.
Snails and slugs: These mollusks can cause significant damage to Calystegia purpurata's foliage. Control measures include handpicking and the use of snail and slug baits that contain iron phosphate. It is also advisable to keep the garden clean and avoid over-irrigation as it creates conditions that favor snails and slugs.
