Light
Bright Indirect Light
Prefers bright, filtered sunlight; shield from direct afternoon sun.
Reference image Deamia chontalensis
Chontales Climbing Cactus
Overview
Deamia chontalensis is an exotic, scrambling, and climbing epiphytic or lithophytic cactus belonging to the family Cactaceae. Known for its segmented, winged stems that cascade beautifully from hanging baskets or cling to supports, it produces magnificent, nocturnal, fragrant white flowers that captivate collectors.
Taxonomy and Naming
This species was historically described under various genera before being placed in the genus Deamia 1. The genus name honors the American botanist Charles C. Deam. The specific epithet chontalensis refers to the Chontales region of Nicaragua, or broadly to regions associated with the Chontal Maya highlands where early specimens and closely related taxa were observed 2.
Distribution and Habitat
Native to southern Mexico (such as Oaxaca and Chiapas) and Guatemala, Deamia chontalensis thrives in seasonally dry tropical biomes 1. In these habitats, it grows as an epiphyte on deciduous forest trees or climbs steep rocky cliffs as a lithophyte, adapting to periods of high humidity followed by dry seasons.
Appearance
The plant features jointed, pendulous green stems with 3 to 6 wavy ribs. Small areoles line the margins, bearing short, fine, yellowish-brown spines. Its most striking feature is the large, nocturnal, funnelform flower, reaching up to 15 cm in diameter, presenting creamy white petals with yellowish outer tepals.
Cultivation
In cultivation, it requires a coarse, highly porous organic potting mix, resembling orchid or epiphytic cactus media. It appreciates bright, filtered sunlight and moderate humidity. Water thoroughly during the active growing season, allowing the top soil layer to dry between waterings, and restrict watering significantly in winter.
Common Cultivation Mistakes
The most prevalent issue is root rot caused by dense, poorly draining soil or overwatering during winter dormancy. Keeping the plant in deep shade results in thin, weak stems and failure to initiate flower buds.
Bibliography
References
Watering
6-20 Days
Water thoroughly once the top soil dries out; reduce drastically in winter.
Soil
Well-drained, organically rich, slightly acidic cactus and potting soil mix
An organic, porous mix of cactus soil, perlite, and orchid bark is ideal.
Safety
Pet Friendly
Features fine spines that can irritate skin; non-toxic but handle with gloves.
Difficulty
Moderate
Moderate; requires attention to seasonal watering cycles and soil aeration.
Native Habitat
Mexico, Guatemala, and Central America
Found scrambling over rocky outcrops and tree trunks in the warm, seasonally dry tropical forests of southern Mexico and Guatemala.
Frequently Asked Questions
Can Deamia chontalensis be grown in a pot indoors?
Yes, it can be successfully grown indoors in hanging baskets or with a trellis to support its climbing habit.
How often should it be watered?
Water every 6 days in summer as the soil dries, and reduce to once every 20 days during the winter dormancy.
What soil mix does it prefer?
It prefers an airy, well-draining organic mix amended with perlite and orchid bark.
Does Deamia chontalensis like direct sun?
It dislikes harsh direct sun; bright, filtered, or indirect light is ideal to prevent sunburn.
Is it toxic to pets?
It is non-toxic, but the fine spines can cause mechanical irritation to pets' mouths or paws.
When and how does it bloom?
It blooms in summer, producing large, fragrant white flowers that open at night.
What is its growth rate?
It has a moderate growth rate, producing cascading or climbing stems under warm and bright conditions.
What is the minimum temperature in winter?
It is sensitive to frost and should be kept above 10°C (50°F) during winter.
Does it require pruning?
Not strictly necessary, but leggy or overgrown stems can be pruned in spring to maintain shape.
Why are brown spots forming on its stems?
Typically caused by overwatering or cold drafts. Reduce watering and ensure excellent drainage.