Overview
Polanisia dodecandra (L.) DC. ssp. dodecandra is a herbaceous flowering plant that belongs to the Cleomaceae family. This species is commonly known as Clammyweed, Redwhisker clammyweed, and Annual clammyweed. The plant is native to North America and can be found in the United States' central and eastern regions, including Texas, Oklahoma, Louisiana, Arkansas, Mississippi, Tennessee, Kentucky, Illinois, Indiana, Ohio, Michigan, and New York.
Appearance
The Polanisia dodecandra plant is characterized by its upright stems that grow to a height of 18-60 inches. The leaves are alternate, simple, and ovate, measuring about 2-4 inches long and 1.2-2 inches wide. The plant flowers from July to October, and its flowers are hermaphrodite (having both male and female organs) and are about 0.2-0.3 inches wide and white in color. The fruit of the plant is a long and narrow capsule that contains numerous black seeds.
Uses
The Polanisia dodecandra plant has several traditional medicinal uses, including being used to treat gastrointestinal disorders, as an antihistamine, and as a diuretic. Some Native American tribes also used the plant to induce sweating and as a blood purifier. The plant is also utilized in gardens as an ornamental plant as its white flowers can be visually appealing.
However, caution is advised when handling the Clammyweed plant as it can produce a sticky resin that causes skin irritation and dermatitis. Therefore, it is advisable to use appropriate precautions when handling the plant, such as wearing gloves and washing exposed skin thoroughly after contact with the plant.
Growth Conditions of Polanisia dodecandra (L.) DC. ssp. dodecandra
Light: The plant requires full exposure to sunlight for optimal growth and should be grown in areas where there is maximum sun exposure. Nonetheless, it can tolerate some shade, especially in hot climates with high UV radiation.
Temperature: The plant can tolerate extreme heat and cold temperatures. However, it grows best in mild climates with temperatures ranging between 21 - 30°C, and a mean annual rainfall of 500 - 900 mm. Areas with temperatures below -5°C and those above 40°C are unsuitable for its growth.
Soil: Polanisia dodecandra grows best in well-drained, sandy or loamy soils. The plant is also capable of tolerating a wide range of soil conditions. Nonetheless, it performs poorly in clay and poorly drained areas, where the roots cannot grow well leading to root rotting. In addition, it thrives in slightly acidic to neutral soils with pH ranging from 6.0 to 7.5.
Irrigation: The plant should be regularly watered to keep the soil moist but not waterlogged. Young plants require frequent watering, while mature plants have higher drought tolerance.
Fertilization: The plant requires little to moderate fertilization because it has adapted to nutrient-deficient soils. Applying compost or organic manure before transplanting can improve the soil structure and promote root growth.
Cultivation methods
Polanisia dodecandra (L.) DC. ssp. dodecandra is a warm-season annual herb that can be grown in a variety of soil types, as long as they have adequate drainage. The plant thrives in full sunlight and prefers warm temperatures.
The seeds of Polanisia dodecandra can be directly sown in the garden once the soil has warmed up. To promote germination, the seeds should be pressed firmly into the soil and watered gently. The plants should be spaced at least 18 inches apart.
Watering needs
Polanisia dodecandra requires moderate watering. The soil should be kept evenly moist, but not waterlogged. Overwatering can lead to root rot, which can damage or even kill the plant. During periods of drought, the plant may need more frequent watering to keep it healthy.
Fertilization
Polanisia dodecandra does not require frequent fertilization. A balanced fertilizer can be added to the soil before planting to provide additional nutrients. If the plant begins to show signs of nutrient deficiencies, such as yellowing leaves or stunted growth, a foliar application of liquid fertilizer can be used.
Pruning
Polanisia dodecandra does not require pruning. However, it is important to remove any dead or diseased branches to prevent the spread of disease. Pinching back the tips of the growing shoots can encourage bushier growth and a fuller plant.
Propagation of Polanisia dodecandra (L.) DC. ssp. dodecandra
Polanisia dodecandra (L.) DC. ssp. dodecandra, commonly known as Clammyweed or Red-whisker Clammyweed, is an annual wildflower native to the southern United States. Its flowers attract native bees, bumblebees, and butterflies, making it a great addition to any garden. If you're interested in propagating Polanisia dodecandra, there are a few methods you can try.
Propagation by seeds
Seeds are the most common way to propagate Polanisia dodecandra. The plant produces small capsule-like fruits that contain the seeds. You can collect the fruit and let it dry out before collecting the seeds. Or you can let nature take its course, and the seeds will disperse on their own.
In either case, the seeds can be sown directly into the ground in the fall or early spring when the soil temperature is above 50°F. Sow the seeds about 1/8 inch deep in well-drained soil that has been raked smooth. Keep the area moist until the seeds germinate, which usually takes about 10-14 days. You can also start the seeds indoors 6-8 weeks before planting outdoors.
Propagation by cuttings
Another way to propagate Polanisia dodecandra is by cuttings. Take cuttings in late spring or early summer from new growth at the end of stems. Cut a 3-4 inch piece of stem and remove the lower leaves. Dip the cut end in rooting hormone and plant it in well-drained soil. Keep the soil moist but not wet and place the cutting in a shaded area until it roots, which usually takes about 2-4 weeks. Once the cutting has rooted, you can transplant it to its permanent location.
Propagation by division
You can propagate Polanisia dodecandra by division in early spring before new growth appears. Dig up the plant and carefully separate the root ball into smaller sections, making sure each section has roots attached. Replant each section in well-drained soil and keep the area moist until new growth appears.
Overall, Polanisia dodecandra is an easy plant to propagate, making it a great choice for beginner gardeners. With a little patience and care, you can create a beautiful display of Clammyweed in your garden.
Disease and Pest Management for Polanisia dodecandra (L.) DC. ssp. dodecandra
Polanisia dodecandra (L.) DC. ssp. dodecandra is a hardy species that is not usually affected by diseases and pests. However, certain factors like environmental stress, poor soil conditions, and improper care can make it susceptible to diseases and pest infestations. The following are some common diseases and pests that might affect the plant and suggested ways to manage them.
Diseases
Fungal Leaf Spots: Fungal leaf spots are caused by several fungi that thrive in warm, humid conditions. Symptoms include black spots on leaves that enlarge and coalesce to form irregular patches. To manage fungal leaf spots, remove and destroy infected leaves and avoid watering the plant from above to prevent water from sitting on the leaves. Apply fungicides if necessary.
Bacterial Leaf Spot: Bacterial leaf spot is a bacterial disease that causes small, water-soaked spots on the leaves. The spots later enlarge and turn brown and may lead to defoliation. To manage bacterial leaf spot, remove and destroy infected leaves and avoid overhead watering. Apply copper-based bactericides if necessary.
Pests
Aphids: Aphids are small, soft-bodied insects that suck the sap from the leaves, causing wilting and stunted growth. To manage aphids, use a strong stream of water to dislodge them from the plants or use insecticidal soaps or oils.
Spider Mites: Spider mites are tiny arachnids that feed on the sap from the leaves, causing discoloration and death of the affected leaves. To manage spider mites, use insecticidal soaps or oils or use predatory insects like ladybugs to control their population.
Caterpillars: Caterpillars are the larvae of moths and butterflies that feed on the leaves and pods of the plant, causing extensive damage. To manage caterpillars, handpick them from the plants if possible or use Bacillus thuringiensis (Bt) spray, which is a natural soil bacterium that kills caterpillars.
Proper care and maintenance of the plant, including regular watering, fertilization, pruning, and sanitation, are essential for keeping the plant healthy and resistant to diseases and pests.
