Columnea

Columnea is a genus of flowering plants in the family Gesneriaceae, comprising a large number of species native to tropical regions of Central and South America. Most Columnea are epiphytic or lithophytic perennials that form hanging or trailing shrubs. They typically have opposite, simple leaves and slender, often branched stems. The flowers are the defining feature: tubular, bilabiate corollas arranged in pendent inflorescences, frequently brightly colored in shades of red, orange, yellow, pink or purple, often with a contrasting throat. Flowering is common under appropriate light and humidity conditions and can occur at different times of the year.

Distribution and habitat

Columnea species are distributed from southern Mexico through Central America and into parts of northern and western South America. They are most diverse in humid montane and cloud forest habitats, where many species grow as epiphytes on trees, sometimes also on rocks or in mossy substrates. The genus exhibits a range of growth forms from compact to sprawling vines, adapted to canopy or understory life.

Cultivation and care

Columnea are popular as ornamental houseplants and, in suitable climates, as outdoor ornamentals. They require bright, indirect light, warm temperatures (generally above 15–18°C), and high humidity. A well-draining, airy growing medium, such as an orchid-like mix or a peat-perlite blend, is recommended. Watering should be steady but not waterlogged, allowing the top of the medium to dry slightly between waterings. They benefit from regular feeding during the growing season. Provide good air circulation and protect from cold drafts and frost.

Propagation and pests

Propagation is typically by stem cuttings or air layering. Common pests include mealybugs, aphids, scale, and spider mites, while overwatering can lead to root rot. Regular inspection and proper cultivation conditions help maintain healthy plants.

Taxonomy

Columnea is placed in the Gesneriaceae family, within the subfamily Gesnerioideae. The genus has undergone taxonomic revisions, with some species moved between related genera as classifications are refined.