Thaumatophyllum xanadu

Natural origin of Thaumatophyllum xanadu

Thaumatophyllum xanadu is native to southern Brazil and Paraguay. It grows in warm areas with a distinct dry season, forming a low, branching plant directly in the ground.

Wild plants form broad, low clumps. The soil becomes wetter after rain and drier between rains.

How to care for Thaumatophyllum xanadu

• Light: Bright filtered light keeps the plant compact and leafy. A little gentle sun is suitable when introduced gradually.
• Watering: Let the top layer become noticeably drier between waterings while the mix deeper in the pot retains some moisture. Water thoroughly and let the excess drain.
• Potting mix: A fertile, well-draining mix that holds some moisture suits this species. Fine bark with pumice or perlite works well.
• Temperature and humidity: A warm home and ordinary household humidity are usually sufficient.
• Feeding: Feed lightly with a complete houseplant fertiliser while new leaves are forming.
• Growth and position: The short branching stems hold the plant upright. Allow room around the pot and turn it occasionally if one side receives most of the light.
• Repotting: Move up a pot size once the roots are crowded or the clump becomes unstable.
• Propagation: Take a stem cutting, or separate a rooted section of the plant once it has enough roots.

Troubleshooting Thaumatophyllum xanadu

• Several lower leaves yellow while the potting mix stays wet: Prolonged wetness can stress the roots and lead to rot. Check the roots before watering again. Remove rotten roots with clean scissors, cutting back to firm healthy roots. Discard what you remove and repot in fresh, well-draining mix. The root rot guide covers the remaining recovery steps.
• New leaf stalks grow longer and the leaves sit farther apart: Too little light is a common cause. Check how much light reaches the plant and move it closer to a bright window gradually if needed.
• Water-soaked or dark brown leaf spots continue to expand: These spots can indicate a bacterial or fungal leaf disease. Isolate the plant, remove badly affected leaves with clean tools and keep the leaves dry. The brown-spots guide can help separate disease from sun, water or physical damage.
• Fine pale speckles, webbing, white wax or small brown bumps appear: These signs can indicate mites, mealybugs or scale. Check the centre of the plant and both sides of the leaves. Keep the plant away from nearby plants while treating it, and follow the product label.

Thaumatophyllum xanadu is toxic to people and pets

• Keep this plant away from children, cats and dogs.
• Its leaves and stems contain insoluble calcium oxalate crystals, which can irritate the mouth, throat, skin and eyes.
• Chewing may cause burning pain, drooling, swelling, vomiting or difficulty swallowing. Contact a veterinarian or medical professional after exposure, especially if swelling or breathing problems occur.

Why is Thaumatophyllum xanadu now called Philodendron xanadu?

Thaumatophyllum means ‘wonder leaf’.

Heinrich Wilhelm Schott established the genus Thaumatophyllum in 1859 in Bonplandia (Hannover), volume 7, page 31.

Thomas Bernard Croat, Simon J. Mayo, and Julius Boos first described it as Philodendron xanadu in 2003 in Aroideana, volume 25, page 63. Cassia Mônica Sakuragui, Luana Calazans, and Simon J. Mayo later placed it in Thaumatophyllum as Thaumatophyllum xanadu in 2018 in PhytoKeys, volume 98, page 65.

Cassia Mônica Sakuragui, Luana Calazans and Simon Mayo revived Thaumatophyllum for this group in 2018 in PhytoKeys, volume 98. Kew’s World Checklist treats Thaumatophyllum xanadu as a synonym of Philodendron xanadu. Both names are still encountered.