Overview of Bidens pilosa L. var. radiata Schultz-Bip.
Bidens pilosa L. var. radiata Schultz-Bip. is also known as Spanish needles, hairy beggartick, and cobbler's pegs. This plant is a member of the Asteraceae family and is native to Central and South America. Currently, it can be found in various parts of Asia, Africa, and Oceania.
General Appearance
The plant is an annual herb that grows up to a height of 1.5 meters. Its leaves are simple, serrated, and arranged oppositely on the stem. The stem is usually green or red in color, upright, and hairy. The flowers are bright yellow and about 1 cm in diameter with numerous ray and disk florets. The plants produce small black or brown seeds that are barbed, enabling the plant to cling to clothing or fur.
Common Uses
Bidens pilosa L. var. radiata Schultz-Bip. is known for its medicinal properties. It contains flavonoids, alkaloids, and essential oils that function as anti-inflammatory, antioxidant, and anti-bacterial agents. The plant is used to treat a variety of ailments such as stomach problems, respiratory infections, and skin disorders. Additionally, it is used in traditional medicine to reduce fever and pain. The plant is also used as a natural dye and as a ingredient in some cuisines.
Light Requirements
Bidens pilosa L. var. radiata Schultz-Bip. is a plant species that prefers full sun exposure, which means it requires at least six hours of direct sunlight per day to grow and thrive. The plant can tolerate partial shade, but it may reduce flowering and affect overall growth. Therefore, it is advisable to grow this plant in an area that receives enough sunlight, such as open fields or gardens that are not shaded by trees or other structures.
Temperature Requirements
Bidens pilosa L. var. radiata Schultz-Bip. is an adaptable plant species that can grow in a wide range of temperatures. The optimal temperature range for this species is between 20-35 °C (68-95 °F). However, it can tolerate temperatures as low as 5 °C (41 °F) and as high as 40 °C (104 °F) in some cases. It is important to note that the plant can be damaged by frost, which can cause the leaves to wither, and the plant may not recover from severe frost damage.
Soil Requirements
Bidens pilosa L. var. radiata Schultz-Bip. prefers well-draining soil that is moist but not waterlogged. It can grow in a wide range of soil types, including sandy, loamy, and clay soils, with a pH range of 6.0-7.5. However, it grows best in slightly acidic soils with a pH range of 6.0-6.5. The plant requires regular watering to maintain soil moisture, but it can tolerate short periods of drought. Fertilization is also recommended, especially during the growing season, to promote healthy growth and flowering.
Cultivation methods
Bidens pilosa L. var. radiata Schultz-Bip. is commonly referred to as Spanish needle, black jack, farmer's friend, and cobbler's pegs. This plant, which belongs to the Asteraceae family, is an annual herbaceous plant that grows to a height of about 2 meters. It is a hardy plant that can adapt to a wide range of environmental conditions.
The plant is mainly cultivated from seeds. The best time to sow the seeds is during the rainy season. The seeds should be sown in well-prepared soil that is rich in organic matter. The recommended spacing for the plants is about 30 cm to 45 cm apart.
Watering needs
Bidens pilosa L. var. radiata Schultz-Bip. requires moderate watering. Over-watering can lead to waterlogging, which can cause root rot. The plants should be watered when the top inch of the soil is dry. Watering in the morning is recommended, as it allows the leaves to dry off before nighttime, which helps to prevent fungal diseases.
Fertilization
Bidens pilosa L. var. radiata Schultz-Bip. can grow in poor soils, but it responds well to fertilization. A balanced fertilizer with equal quantities of nitrogen, phosphorus, and potassium is suitable for the plant. The fertilizer should be applied at intervals of 2 to 3 weeks during the growing season. However, it is important not to over-fertilize the plant, as this can lead to excessive foliage growth, which can reduce the yield of the plant.
Pruning
Bidens pilosa L. var. radiata Schultz-Bip. does not require extensive pruning. However, to promote bushier growth, the plant should be pinched back when it reaches a height of about 30 cm. This encourages the plant to produce lateral branches, which can lead to a more compact and fuller plant. Additionally, removing dead or damaged leaves and stems can improve the appearance of the plant and prevent diseases from spreading.
Propagation of Bidens pilosa L. var. radiata Schultz-Bip.
Bidens pilosa L. var. radiata Schultz-Bip. can be propagated through various methods including seeds, cuttings, and division.
Seeds
Seeds are the easiest way to propagate Bidens pilosa L. var. radiata Schultz-Bip. The seeds can be sown directly in the field or in seed trays. Seeds should be sown in well-draining soil, and covered with a light layer of soil or sand. The soil should be kept moist until the seedlings emerge, which usually takes 2-3 weeks.
Cuttings
Bidens pilosa L. var. radiata Schultz-Bip. can also be propagated through stem cuttings. Cuttings of about 10-15 cm long can be taken from the plant and placed in a well-draining potting mix. The mix should be kept moist and placed in a shaded area until the cuttings start to root, which usually takes about 2-3 weeks. Once rooted, the plants can be transplanted into the field.
Division
Bidens pilosa L. var. radiata Schultz-Bip. can be propagated through division as well. Older plants can be dug up and divided into smaller clumps, each containing a few stems and roots. These clumps can then be replanted in a well-draining soil and kept moist until new growth appears.
Disease and Pest Management for Bidens pilosa L. var. radiata Schultz-Bip.
Bidens pilosa L. var. radiata Schultz-Bip., also known as Spanish needle, is a herbaceous plant in the Asteraceae family that is widely distributed throughout the world. It is often considered a weed, but it has some medicinal properties and is used as a vegetable in some cultures. As with any plant, Bidens pilosa is susceptible to several diseases and pests that can negatively affect its growth and yield. Proper disease and pest management techniques are essential to maintain viable and healthy growth.
Common Diseases
Bidens pilosa can be susceptible to various diseases caused by fungi, bacteria, and viruses.
- Alternaria leaf spot: Alternaria alternata can cause brown circular spots on the leaves, leading to defoliation and plant weakening. To manage this disease, remove infected parts and spray with fungicide.
- Anthracnose: Colletotrichum gloeosporioides can cause lesions on leaves, stems, and fruits leading to stunted growth and yield reduction. To manage this disease, remove infected parts, apply fungicide and improve drainage.
- Powdery mildew: Erysiphe cichoracearum can cause a white powdery appearance on leaves and stems. This disease can reduce photosynthesis and cause early defoliation. To manage this disease, spray with fungicides and improve air circulation and plant spacing.
- Root rot: Fusarium spp. can cause root rot, leading to wilting and death of the plant. To manage this disease, provide proper drainage, remove infected plants, and treat the soil with fungicide.
Common Pests
Bidens pilosa can also be affected by different pests that can cause damage to leaves, stems, and flowers.
- Aphids: These tiny insects can suck sap from the plant, causing wilted and curled leaves. To manage this pest, spray with insecticidal soap or neem oil.
- Caterpillars: These larvae can eat leaves and fruits, causing extensive damage. To manage this pest, manually remove caterpillars, use Bacillus thuringiensis, or try organic methods like planting companion plants.
- Mites: Spider mites can cause yellowing and stippling of the leaves, leading to defoliation. To manage this pest, spray with insecticidal soap or neem oil and improve humidity levels.
- Trips: These small insects can damage leaves and flowers, causing distortion and mottling. To manage this pest, use sticky traps, remove weeds, and improve sanitation practices.
Integrated pest management techniques should be considered to prevent or manage diseases and pests in Bidens pilosa L. var. radiata Schultz-Bip.. Planting disease-resistant varieties, using proper cultural practices, and regularly monitoring the plants can also help in achieving good plant health.
