Bidens Pilosa

Description

Bidens Pilosa, also known as Spanish Needle or Black Jack, is a flowering plant that belongs to the Asteraceae family. It is native to South America but can now be found in tropical and subtropical regions worldwide. This annual or perennial herb grows up to 3 feet tall and has a hairy, upright stem. Its leaves are simple and serrated, with a dark green color and a rough texture. The flower heads are small and yellow, with a diameter of 0.5 to 1 inch. The plant produces small, black seeds with barbed awns that easily attach to clothing or animal fur.

Taxonomic Information

Appearance

Bidens Pilosa has a distinctive appearance, with its hairy stem and serrated leaves. The leaves are arranged alternately along the stem, and the plant produces small yellow flowers that bloom from summer to fall. The flower heads are surrounded by several rows of bracts, which are leaf-like structures that protect the flowers. The plant produces small, black seeds that have barbed awns that can attach to clothing or animal fur.

Care Guide

Bidens Pilosa is relatively easy to care for and can thrive in a variety of growing conditions. Here are some tips for caring for this plant:

• Water: Bidens Pilosa prefers moist soil but can tolerate some drought. Water the plant when the top inch of soil feels dry to the touch.
• Fertilization: Use a balanced fertilizer once a month during the growing season.
• Soil: Bidens Pilosa prefers well-draining soil with a pH between 6.0 and 7.0.
• Sunlight: This plant prefers full sun but can tolerate some shade.
• Hardiness Zones: Bidens Pilosa is hardy in USDA zones 9-11 but can be grown as an annual in cooler climates.

Common Pests & Diseases

Bidens Pilosa is relatively resistant to pests and diseases. However, it can be susceptible to the following:

• Aphids: These small insects can cause damage to the plant by sucking sap from the leaves. Use insecticidal soap or neem oil to control aphids.
• Leaf spot: This fungal disease can cause yellow or brown spots on the leaves. Remove infected leaves and use a fungicide if necessary.
• Root rot: This disease can be caused by overwatering or poorly drained soil. To prevent root rot, make sure the soil is well-draining and avoid overwatering.

Habitat

Bidens Pilosa is native to South America but can now be found in tropical and subtropical regions worldwide. It grows in a variety of habitats, including fields, roadsides, and disturbed areas. The plant prefers full sun but can tolerate some shade and can grow in a range of soil types.

Question and Answer

Q: Is Bidens Pilosa a weed?
A: Bidens Pilosa can be considered a weed in some areas due to its ability to spread quickly and its barbed seeds that can attach to clothing or animal fur.

Q: Can Bidens Pilosa be grown indoors?
A: Bidens Pilosa can be grown indoors if provided with bright light and well-draining soil.

Q: Can Bidens Pilosa be used for medicinal purposes?
A: Bidens Pilosa has been used in traditional medicine to treat a variety of ailments, including respiratory infections, skin conditions, and digestive problems.

Q: Is Bidens Pilosa toxic to pets?
A: Bidens Pilosa is not known to be toxic to pets, but the barbed seeds can cause irritation if they become embedded in the skin or fur.

Related Plants

• Bidens Alba
• Bidens Aristosa
• Bidens Cernua
• Bidens Frondosa
• Bidens Laevis

References

• “Bidens pilosa.” Missouri Botanical Garden, www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=c940. Accessed 2 Dec. 2021.
• “Bidens pilosa.” Plants of the World Online, www.plantsoftheworldonline.org/taxon/urn:lsid:ipni.org:names:185197-1. Accessed 2 Dec. 2021.
• Wu, Ming-Jen, et al. “Bidens pilosa: A Dominant Plant Species in Traditional Taiwanese Herbal Medicine.” Journal of Traditional and Complementary Medicine, vol. 2, no. 1, 2012, pp. 41-46., doi:10.1016/s2225-4110(16)30056-4.