The Bottle-brush Orchid (Arpophyllum giganteum) is an epiphytic species native to moist and mountainous forests at altitudes of 350 to 2,100 meters (1,148 to 6,890 feet), spanning the equatorial region that includes Mexico, Central America, Venezuela, and Colombia. At first glance, it stands out due to its dense, cylindrical inflorescences with numerous tiny lilac flowers. This particular characteristic has earned it popular names such as “bottle-brush” and “bottle-brush orchid”.
This orchid is rhizomatous, growing sympodially, and forms full and wide clumps. The pseudobulbs are elongated, cylindrical in shape, flattened on the sides, and wrapped in tubular bracts. The leaves are lanceolate, leathery, and scythe-shaped. The genus name Arpophyllum is derived from the Greek words “Arpo,” meaning scythe, and “phyllum,” meaning leaf. Flowering occurs at the end of winter and the beginning of spring, lasting about 20 days. The inflorescences are raceme-type, erect, cylindrical, up to 40 cm (15.7 inches) long, with tiny flowers opening in a spiral from the base to the top, gradually.
The flowers of this species do not undergo resupination, a common movement in most orchids where the flower repositions itself so that the labellum is downward and slightly horizontal, aiding in pollination. The flowers of A. giganteum are pink to lilac, with the labellum being a more intense shade. This species has three subspecies:
- Arpophyllum giganteum subsp. alpinum
- Arpophyllum giganteum subsp. giganteum
- Arpophyllum giganteum subsp. medium
The cultivation difficulty level of this orchid is considered moderate. Although initially quite rare in Brazil and slow-growing, it is now increasingly included in orchid enthusiasts’ collections and can be easily acquired at large exhibitions or even online from specialized sites. It is undoubtedly a unique species that adds special charm to any collection. It is recommended for intermediate and advanced orchid enthusiasts.
It should be grown under filtered light or partial shade, with ideal shading of 50 to 70%, in a well-draining substrate specifically for epiphytic orchids, but kept moist. Water abundantly throughout the year, reducing watering after the full development of the leaves and during flowering. A substrate suggestion includes a mix of barks (coconut, pine, etc.) and charcoal. Fertilize every 15 days with orchid-specific fertilizers, preferably liquid, applied through foliar spraying.
The Bottle-brush Orchid prefers a mild climate, with annual averages between 10 and 29°C (50 to 84°F), i.e., cool and well-ventilated, but is sensitive to frost. It can be easily propagated by dividing the clumps, ensuring each new division has a complete structure (roots, rhizome, pseudobulbs, and a growth point) and at least three mature and healthy pseudobulbs. Use plastic, ceramic, or wooden pots and repot when the substrate begins to deteriorate, as soon as the plant starts new growth in the cycle.
