Overview
Bidens nematocera (Sherff) Sherff, commonly known as the cernuous bur-marigold, is a perennial herbaceous plant belonging to the family Asteraceae. It is native to the Southeastern United States and can be found from Virginia to Florida and westward to Louisiana.Common Names
Bidens nematocera goes by several common names, including cernuous bur-marigold, southern bur-marigold, and southern beggarticks.Appearance
The plant grows up to 3 feet tall and spreads up to 2 feet wide. It has thin, branching, green stems with alternate leaves that are between 1 to 3 inches long and serrated or cleft along their margins. The leaves have a dark green color and are arranged opposite each other on the stem. The flowers of Bidens nematocera are small and yellow, approximately 1 inch in diameter, and bloom in late summer and early fall. They grow on branched inflorescences at the tip of the stem. The plant produces small, black, needle-shaped seeds that are covered in barbs or hooks, which is where it gets its common name as bur-marigold.Uses
Despite being considered a weed in some areas, Bidens nematocera has some medicinal properties. The plant contains essential oils, flavonoids, and alkaloids that have been used to treat digestive problems, coughs, and colds. Its leaves and stems can also be used to make tea, which is said to have anti-inflammatory and pain-relieving effects. In addition to its medicinal uses, Bidens nematocera is also used in landscaping as ground cover or for erosion control. The yellow flowers attract pollinators such as bees and butterflies, making it a popular choice for gardens and natural areas.Growth Conditions for Bidens nematocera (Sherff) Sherff
Bidens nematocera (Sherff) Sherff, commonly known as bur marigold, is a native plant found throughout North and Central America. It is a hardy plant that can thrive in a range of environmental conditions. However, to ensure optimal growth, certain conditions must be met.
Light Requirements
Bur marigold is a sun-loving plant that requires a minimum of six to eight hours of direct sunlight per day. In areas with intense heat, partial shade may be necessary to protect the plant from sunscorch or dehydration.
Temperature Requirements
Bur marigold prefers moderate to cool temperatures, with an average temperature range between 50 and 75 Fahrenheit (10 to 24 Celsius). High temperatures can cause the plant to become stressed and wilt, so it is crucial to keep it cool in warmer months.
Soil Requirements
Bur marigold thrives in damp, fertile soils with a pH ranging from slightly acidic to neutral (5.5 to 7.5). The soil must be well-draining, as water-logged soil can cause root rot and other fungal diseases. Adding organic matter to the soil improves drainage and nutrient availability, enabling the plant to grow and thrive.
Fertilization Requirements
Bur marigold is a fast-growing plant that requires regular fertilization to maintain healthy growth. Apply a balanced fertilizer (10-10-10) to the soil every four to six weeks during the growing season. Ensure that the fertilizer evenly distributes, avoiding direct contact with the stems or leaves.
Cultivation Methods
Bidens nematocera is best cultivated in a well-draining soil with a pH level between 5.5 to 6.5. The plant prefers a sunny location but can tolerate some shade. It is also essential to provide the plant with space, as it tends to spread out relatively quickly. Unlike other plants, Bidens nematocera can thrive in a wide range of temperatures and humidities, making it an excellent addition to any garden.
Watering Needs
Bidens nematocera needs to be watered regularly to thrive. However, care must be taken not to overwater the plant, as it can cause significant damage and even death. The soil needs to remain moist but not waterlogged, and the best way to determine whether it needs watering or not is by checking the soil's moisture level by sticking your finger into the soil 1-2 inches. Water the plant deeply when the top layer of soil feels dry to the touch.
Fertilization
The Bidens nematocera plant requires regular fertilization to maintain its health and vibrancy. Use a balanced slow-release fertilizer during the growing season, and apply it every four to six weeks. Water-soluble fertilizers can also be used, but they should only be applied every two weeks during the growing season. A lack of fertilizer can result in slow growth, leaf yellowing, and poor flowering.
Pruning
Bidens nematocera requires occasional pruning to keep it tidy and promote bushier growth. Pinch back the tips of the plant stems to encourage branching and more flowers. Deadhead spent flowers to encourage prolific blooms and prevent seed production. While the plant is relatively low maintenance, pruning it regularly can keep it looking its best and extend its lifespan.
Propagation of Bidens nematocera (Sherff) Sherff
Bidens nematocera (Sherff) Sherff, commonly known as "needleleaf Spanish needle", can be propagated through seeds and cuttings.
Propagation through seeds
The best time to collect seeds for propagation is when the plant has fully ripened. The seeds can then be stored in a dry and dark space until planting season. Before sowing, the seeds can be soaked in water overnight to improve germination rates.
Plant the seeds in well-draining soil or potting mix, ensuring that the soil is moist and warm. Cover the seeds with a thin layer of soil and keep them in a warm and sheltered spot. Germination typically occurs within 7-14 days.
Once the seedlings have grown their first set of leaves, they can be transplanted into individual pots or directly into the garden.
Propagation through cuttings
Bidens nematocera (Sherff) Sherff can also be propagated through softwood cuttings taken from the plant during the growing season. Cuttings should be taken from the tip of the stem and should be around 4-6 inches long.
Remove the leaves from the bottom half of the cutting and dip the cut end into rooting hormone. Place the cutting into a pot filled with moist potting mix and keep it in a sheltered spot away from direct sunlight. Mist the cutting regularly to keep the soil moist and encourage root growth.
The cutting should root within 4-6 weeks. Once it has developed a strong root system, it can be transplanted into a larger pot or into the garden.
Disease Management
Bidens nematocera is relatively disease-resistant, but it is still susceptible to some fungal and viral diseases.
Mildew: Powdery mildew is perhaps the most common fungal disease that affects Bidens nematocera. The plant appears to be white or gray with a powdery coating. To manage this disease, avoid getting water on foliage, thin out plants to improve air circulation, and apply a fungicide if necessary.
Leaf Spot: If the plant has yellow spots on the leaves, it may be suffering from a leaf spot disease. Remove and destroy infected leaves and avoid getting water on foliage.
Viruses: Viruses can cause yellow or mottled leaves, stunted growth, and distorted flowers. Infected plants should be removed and destroyed as soon as possible, and insects that transmit viruses should be controlled.
Pest Management
Bidens nematocera is prone to insect infestations, but regular monitoring and control measures should prevent any serious damage.
Aphids: These tiny insects suck sap from the plant, causing leaves to curl and yellow. To manage aphids, hose them off with water or apply insecticidal soap.
Spider Mites: Spider mites can cause yellow speckling on leaves, and heavy infestations can cause the plant to become completely covered in webs. Spider mites thrive in hot and dry conditions, so keep the plant well-watered and use a miticide if necessary.
Thrips: Thrips are tiny insects that suck sap from leaves, causing a silver or bronze sheen on the foliage. They can also transmit viruses. Use yellow sticky traps to monitor for thrips and apply an insecticide if necessary.
