Overview
Brasenia purpurea (Michx.) Casp., commonly known as water shield, is a floating aquatic plant found in North America. This plant is known for its beautiful lilac flowers and its edible fruit.
Origin and Distribution
Water shield is native to North America, where it can be found in freshwater lakes and marshes. Its range extends from Florida to Quebec in the east and from Texas to North Dakota in the west. It is also found in eastern Asia.
Common Names
Water shield is also known by a variety of other names, including American water lotus, water target, and dollar bonnet.
General Appearance
Water shield is a floating plant that can grow up to 30 cm in length. The leaves of the plant are round and can grow up to 15 cm in diameter. The leaves are dark green on top and purple underneath. The flowers of the water shield are small and pink or lilac in color. The fruit of the plant is a small, purple berry that is edible and has a nutty flavor.
Uses
The fruit of the water shield is edible and has been used as a food source by Indigenous peoples. The plant is also used as an ornamental plant in water gardens. In addition, the plant has been found to have medicinal properties, and has been used to treat fevers, diarrhea, and inflammation. The plant is also known to have antibacterial and anti-inflammatory properties.
Growth Conditions of Brasenia purpurea (Michx.) Casp.
Brasenia purpurea (Michx.) Casp., commonly known as the water shield, is an aquatic perennial plant that typically grows in shallow freshwater. This plant is native to North America, particularly in regions with slow-moving or still water bodies such as ponds and lakes.
Light Requirements
The growth of Brasenia purpurea (Michx.) Casp. is significantly affected by the amount of light it receives. This plant prefers a moderate amount of light and can tolerate some shading. However, excessive shade leads to reduced growth and negatively impacts its reproduction and overall survival.
Temperature Requirements
The growth of Brasenia purpurea (Michx.) Casp. is also dependent on the water temperature. This plant thrives in water temperatures between 10°C to 25°C. Temperatures below 10°C hinder growth, while temperatures above 25°C cause the plant to die off in the late summer months.
Soil Requirements
Since Brasenia purpurea (Michx.) Casp. is an aquatic plant, soil is not technically applicable to its growth. Instead, this plant requires special adaptation for rooting in water, primarily in a muddy, sandy substrate at the bottom of the shallow freshwater where it grows.
Furthermore, the water quality is fundamental for its growth as it needs sufficient nutrients such as carbon, nitrogen, and phosphorous for photosynthesis. The ideal pH range for the growth of Brasenia purpurea (Michx.) Casp. is between 6.5 to 7.5. Water pollution, particularly from agricultural and industrial sources, results in toxicities that affect the plant's ability to perform photosynthesis, according to studies.
Cultivation
Brasenia purpurea is a North American aquatic perennial plant that grows in shallow lakes, slow-moving streams, and ponds. It requires a lot of sunlight to thrive and prefers still or slow-moving water bodies with temperatures between 15-25°C. The rhizomes of the Brasenia purpurea have naturally high levels of hormones and nutrients that help the plant grow healthily. Therefore, it can self-propagate through rhizome division.
Watering Needs
The Brasenia purpurea requires a consistent amount of water to grow well. It can tolerate a range of water qualities from soft to hard, but the water should be pH neutral to slightly alkaline for optimal growth. You should not let the plant dry out completely as it can cause the foliage to wilt, while overwatering can lead to the plant's death.
Fertilization
Since Brasenia purpurea typically grows in nutrient-rich conditions, it requires a good supply of nutrients to thrive. You can use fertilizer spikes formulated for aquatic plants that offer significant benefits for the plant's growth rate. Fertilizers provide necessary nutrients that can help plants grow faster and inhibit algae growth in aquatic environments. You should apply liquid fertilizer once a month or every other month at one-quarter strength to avoid over-fertilizing.
Pruning
Brasenia purpurea requires very little pruning since it is not a very tall plant. It grows to a maximum height of 2-3 feet, with foliage extending to the surface of the water. You only need to remove any dead, decaying, or yellowing leaves and stems from the plant regularly to prevent the buildup of decaying material. However, if the plant grows too much towards one side, you can trim some of the longer stems to redistribute the weight and balance the plant. Trim the stem off just above the waterline to avoid damaging the plant.
Propagation of Brasenia purpurea (Michx.) Casp.
Brasenia purpurea, commonly known as purplish water shield, is a freshwater aquatic plant that is native to North America. Propagation of this plant can be achieved through several methods, including:
Seed propagation
The most common method of propagation for Brasenia purpurea is through seeds. Seeds are produced in late summer and fall and can be collected once they have ripened and turned brown. Seeds should be stored in cool, dry conditions until they are ready to be planted in the spring.
To plant the seeds, they should be scattered liberally on the bottom of shallow containers filled with water and placed in a sunny location. The water should be changed weekly, and the seeds will typically germinate within 1-2 weeks.
Division propagation
Another method of propagation for Brasenia purpurea is through division. As the plant grows, it forms rhizomes that can be separated and replanted to produce new plants. This method is best done in the spring when the plant is actively growing.
To divide the plant, gently dig up the plant and carefully separate the rhizomes. Replant the separated rhizomes in their own containers filled with water and place them in a sunny location. Change the water weekly until new growth appears.
Cuttings propagation
Propagation by cuttings is not the most common method of propagating Brasenia purpurea but can be successful if done correctly. Stem cuttings should be taken in midsummer and planted in a container filled with water. The container should be placed in a sunny location and the water should be changed weekly. The cuttings will begin to grow roots within 1-2 weeks.
In conclusion, Brasenia purpurea can be propagated through seed, division, and cuttings. By using any of these methods, it is possible to produce new plants that will thrive in a freshwater aquatic environment.
Disease and Pest Management for Brasenia purpurea
Brasenia purpurea is a vulnerable plant species that can be affected by different types of diseases and pests. Proper management strategies can help in controlling the damage caused by these diseases and pests. Here are some common diseases and pests that affect Brasenia purpurea and ways to manage them:
Common Diseases
1. Downy Mildew
Downy mildew is a common fungal disease that affects Brasenia purpurea. Symptoms include yellowing and curling of leaves, stunted growth, and white or grayish patches on the underside of the leaves. To manage downy mildew, remove infected leaves and avoid wetting the foliage while watering. Use fungicides as a last resort.
2. Rust
Rust is a fungal disease that appears as small, reddish-brown spots on the leaves of Brasenia purpurea. The spots may merge to form larger patches, and the leaves may eventually turn yellow and fall off. To prevent rust, avoid overcrowding the plants and maintain good air circulation. Remove infected leaves and use fungicides if necessary.
3. Anthracnose
Anthracnose is a fungal disease that causes small, sunken brown spots on the leaves of Brasenia purpurea. The spots may merge to form irregularly shaped patches, and the leaves may curl and fall off. To prevent anthracnose, avoid wetting the foliage while watering, and remove infected leaves. Use fungicides as a last resort.
Common Pests
1. Caterpillars
Caterpillars are common pests of Brasenia purpurea that can cause extensive damage to the leaves and stems. To manage caterpillars, remove them by hand or use insecticidal sprays containing Bacillus thuringiensis.
2. Aphids
Aphids are small, soft-bodied insects that suck sap from the leaves of Brasenia purpurea. The leaves may curl and turn yellow, and the plant may become weak and stunted. To manage aphids, remove them by hand or use insecticidal soaps or neem oil.
3. Snails and Slugs
Snails and slugs can cause extensive damage to Brasenia purpurea by eating the leaves and stems. To manage snails and slugs, remove them by hand or use baits containing iron phosphate or metaldehyde.
Implementing good cultural practices, such as proper watering and fertilization techniques, can also help in preventing diseases and pests from attacking Brasenia purpurea. Regular monitoring and early detection of diseases and pests are essential in managing the damage caused by them.
