Bidens (Bi’dens), most commonly known as Spanish needles, is a generic name for several flowering plants belonging to the Asteraceae family.
The name, Bidens, comes from an amalgamation of two Latin words – “Bis,” which means “two,” and “Dens,” which means “tooth.”
The name refers to the flowers or fruits of these plants that barbed and usually have two pappi at the end. It is interesting to know that on the Hawaii islands, where some species face a threat of extinction, these plants are locally known as kokoʻolau or koʻokoʻolau.
Keep in mind that there are around 250 species of Bidens. Therefore, it does not come as a surprise that these plants are distributed all over the world.
They are found in tropical regions where they enjoy the sunny tropical weather. While most Bidens species grow in Africa and America, they are also found in parts of Europe and Asia. Some of the most popular species of Bidens include:
- Bidens alba
- Bidens amplectens
- Bidens amplissima
- Bidens aurea
- Bidens beckii
- Bidens bipinnata
- Bidens chippii
- Bidens coronata
- Bidens pilosa
- … and many more.
Bidens Plant Care
Size & Growth
Bidens are perennial plants that generally grow to 12″ – 16″ inches in height and 1′ – 3′ feet in width. However, the height may vary a bit depending on the species of the plant.
Flowering and Fragrance
Bidens are flowering plants. The flowers are usually yellow, but white, pink, red, and orange-colored Bidens also exist. The blooming season starts in April, resulting in abundant flowers. These plants enjoy a long blooming season that lasts till October.
Light & Temperature
Native to tropical weather, Bidens enjoy the sun and require a lot of sunlight to bloom. The more light they receive, the more flowers they will produce in the blooming season.
The ideal day time temperature for Biden plants ranges from 64° – 75° degrees Fahrenheit. Maintain nighttime temperatures around 55° – 65° degrees Fahrenheit.
If Bidens are grown outdoors, protect your plants and move them indoors or out of chilly winds once the temperature starts to drop.
Watering and Feeding
Bidens are low-maintenance plants that do not require a lot of water.
Water Biden plants when the soil is dry or notice that the plant may be suffering due to lack of watering. It is also a good idea to water these plants only on days of high temperature.
Feeding can help Biden’s bloom. Therefore, if you love flowers, use an organic flower plant fertilizer to feed your plants during the spring. It will help them produce more flowers. It is best to opt for balanced fertilizers that contain average micronutrient levels.
Soil & Transplanting
Bidens grow best in well-drained soil. Also, they enjoy neutral soil, which is loaded with organic matter or Hummus. The ideal pH range for Bidens ranges from 5.5 to 6.3.
More on Soil Fertility
Grooming and Maintenance
Under the right conditions, these plants require little pampering. It is a good idea to prune or pinch them to encourage dense and fuller-looking plants. Also, once the flowering season is over, don’t forget to remove dead leaves and flowers.
Propagating Bidens Plants
Propagate Bidens plants through seeds. Keep in mind that these plants are zoochorous, which means that the seeds of these plants can get stuck to feathers, fur, and even clothing and get transported to their new habitat.
When sowing Biden seeds, choose a sheltered place and maintain temperature to about 66° degrees Fahrenheit.
You can also propagate these plants through cutting or division. The best time of the year to propagate Bidens through these methods is during the summer.
Bidens Plants Pest or Diseases
Bidens are susceptible to Pythium and botrytis diseases, both handled by using a good-quality fungicide. Another problem that Biden owners may encounter is frosting during the colder months.
The only way to keep your plants healthy during the winter is to maintain a temperature above 40° F at all times. Also, refrain from overwatering your plants as it can cause the roots to rot and eventually kill the plant.
Suggested Biden Plants Uses
Biden plants have great foliage and bear beautiful flowers. These plants are generally grown as ornamental plants, especially the species that produce white Biden flowers.
While these plants do well in containers, it is common to spot them in a border. You can also pair them with lovely Petunias to enjoy a colorful summer!