4.2. Caudex Delonix Decary (Madagasca bottle tree) 7688

🌿 Delonix decaryi, the Madagascar bottle tree, belongs to the Fabaceae family and is endemic to the xerophytic shrubland and open woodland of southern and southwestern Madagascar near Toliara. In its native habitat it grows as a small, swollen-trunked tree. It is listed as Vulnerable by the IUCN and is a collector-level houseplant admired for its dramatic bottle-shaped trunk.
FUN FACT
This species' trunk can swell to a bottle-like 80 centimetres in diameter despite the tree itself only reaching 3 to 10 metres tall — a dramatic water-storage adaptation for surviving Madagascar's long dry seasons, with grey bark that peels away in fragments as it matures.
FOLIAGE AND GROWTH HABIT
This pachycaul (thick-trunked) tree forms an umbrella-shaped crown atop its swollen, bottle-shaped base. It is deciduous, dropping its leaves during cooler, drier months and regrowing them as conditions warm.
FLOWER DETAILS
Flowers are white, fragrant, and showy, growing up to 7.5 cm wide with long, striking red stamens. As the blooms age, their four petals shift from white toward yellowish or apricot tones.
CARE INSTRUCTIONS
🌞 Light: Light shade to full sun throughout the year suits this species.
💧 Water: Water plentifully during summer, then keep it rather dry over winter.
🌡️ Humidity: Average humidity is fine; good drainage matters more than air moisture.
🪴 Soil: Rich, very well-draining, preferably stony soil suits its caudiciform roots.
🏺 Potting: A sturdy pot with excellent drainage supports the swelling trunk; keep it above about 12°C in winter, since it dislikes cold, wet conditions.
🌱 Growth rate: Slow, as is typical for pachycaul, caudex-forming trees.
👩‍🌾 Fertilizing: Feed lightly during the active summer growing season.
WHERE TO PUT IT
A bright, sunny spot with warmth suits this bottle-trunked tree well. Protect it from cold, damp winter conditions, which pose the biggest risk to its health.