Catasetum

Description

Catasetum is a genus of orchids that is native to Central and South America. It was first described by John Lindley in 1839 and currently includes around 160 species. Catasetum is a monopodial orchid, which means that it has a single stem that grows vertically and produces leaves and flowers along its length. It is a popular ornamental plant due to its unique and showy flowers, which come in a range of colors such as yellow, green, brown, and red.One of the most interesting features of Catasetum is its unique reproductive system. Unlike most orchids that rely on pollinators such as bees or butterflies, Catasetum has evolved to attract male euglossine bees. The male bees are attracted to the orchid’s fragrant scent and colorful flowers, and when they land on the lip of the flower, they trigger the release of a sticky, glue-like substance that attaches to their body. As the bee flies away, the pollinia (pollen packets) are removed from the flower and attached to the bee’s body, which are then transferred to the next flower it visits.

Taxonomic Information

Appearance

Catasetum orchids are known for their large and showy flowers, which can grow up to 15 cm in diameter. The flowers have a distinctive lip that is fringed and spotted, and a column that is elongated and curved. The leaves of Catasetum are plicate (pleated) and can grow up to 50 cm long. The pseudobulbs are thick and cylindrical, and can reach up to 60 cm in length. The overall height of a mature Catasetum plant can range from 30 cm to over 1 meter, depending on the species.

Care Guide

Catasetum orchids require specific care to thrive. Here are some important factors to consider:Water: Catasetum orchids prefer to be kept moist but not wet. They require more water during the growing season (spring and summer) and less during the dormant season (fall and winter).Fertilization: Catasetum orchids require regular fertilization during the growing season with a balanced fertilizer (e.g. 20-20-20). They also benefit from a monthly application of magnesium and calcium.Soil: Catasetum orchids prefer a well-draining mix that contains bark, perlite, and sphagnum moss. They should be repotted every 2-3 years.Sunlight: Catasetum orchids require bright but indirect sunlight. They can tolerate some direct sun, but too much can cause leaf burn.Hardiness Zones: Catasetum orchids are not tolerant of cold temperatures and should be kept in a warm environment (minimum 15°C). They are best suited for USDA hardiness zones 10-11.

Common Pests & Diseases

Catasetum orchids are susceptible to a range of pests and diseases, including:Spider mites: These tiny pests can cause leaf yellowing and discoloration. They can be controlled with insecticidal soap or neem oil.Scale insects: These pests can cause leaf drop and stunted growth. They can be controlled with a systemic insecticide.Root rot: This disease is caused by overwatering or poor drainage. It can be prevented by using a well-draining potting mix and allowing the soil to dry out between waterings.

Habitat

Catasetum orchids are native to Central and South America, where they grow in a range of habitats such as rainforests, cloud forests, and savannas. They are epiphytes, meaning that they grow on other plants (such as trees) without harming them. Catasetum orchids are adapted to grow in bright but indirect sunlight and require high humidity to thrive.

Question and Answer

Q: How often should I water my Catasetum orchid?
A: Catasetum orchids prefer to be kept moist but not wet. Water them thoroughly once a week during the growing season and less frequently during the dormant season.Q: How do I fertilize my Catasetum orchid?
A: Use a balanced fertilizer (e.g. 20-20-20) and apply it once a week during the growing season. You can also add magnesium and calcium supplements once a month.Q: How do I repot my Catasetum orchid?
A: Repot your Catasetum orchid every 2-3 years using a well-draining potting mix. Gently remove the plant from its pot and trim any rotting roots. Place it in the new pot and fill with fresh potting mix.Q: Can Catasetum orchids tolerate direct sunlight?
A: Catasetum orchids prefer bright but indirect sunlight. They can tolerate some direct sun, but too much can cause leaf burn.

Related Plants

Here are some related orchid genera that you might be interested in:

• Encyclia
• Epidendrum
• Cattleya
• Miltonia
• Oncidium

References

• Christenson, E. A. (2001). Catasetum. Flora Neotropica, 81(1), 1-202.
• Sheehan, T. J., & Ackerman, J. D. (1988). Bateman’s principle and Catasetum behavior: the relationship between floral morphology and pollinator behavior in seven Catasetinae (Orchidaceae). American Journal of Botany, 75(10), 1486-1497.
• Stewart, J., & Griffith, M. P. (2020). Catasetum Lindl. In The Orchids of South Central America: An Introduction, Volume 1 (pp. 223-235). Springer International Publishing.