Microchilus argenteus

Botanical identity and natural origin of Microchilus argenteus

Microchilus argenteus is native to eastern and southern Brazil and Paraguay, where it grows as a terrestrial orchid in wet tropical forest. It grows on shaded forest ground rich in organic matter and deep leaf litter. It is also known by its older botanical name, Aspidogyne argentea.

Care for Microchilus argenteus

• Light: Keep it in low indirect light.
• Temperature and humidity: Keep temperatures around 18–24 °C. Avoid prolonged temperatures below 15 °C. Aim for 60–80% humidity while keeping some air moving around the plant. Keep it at stable warm indoor temperatures, with high humidity and gentle airflow.
• Water: Keep the mix lightly and evenly moist. Water before it dries out completely and let excess water drain away.
• Potting mix: Use an airy orchid mix for soil-growing orchids that stays slightly moist around the fine roots. Fine bark with perlite or pumice and a little fine potting mix works well.
• Feeding: Apply a dilute orchid fertiliser while new leaves and rhizome growth are developing. Reduce feeding as growth slows.
• Repotting: A shallow, wider pot gives the creeping rhizome room to extend. Repot when the mix begins to break down, drainage becomes slow, or the rhizome reaches the pot edge.
• Propagation: Divide an established rhizome into sections with healthy roots and at least one active shoot.

Problems with Microchilus argenteus

• Leaf edges become dry or brown: The root zone has dried too far or fertiliser salts have built up. Water thoroughly and let the pot drain. If you feed often, reduce the amount or frequency.
• Leaves or rhizome become yellow, translucent or soft: The mix has stayed too wet, so the roots and rhizome are getting too little air. Remove the plant from the pot, cut away rotten tissue to firm healthy tissue with a clean tool, discard the removed rotten tissue, and repot in fresh airy mix.
• New leaves are small and growth is weak: Low light or old potting mix can slow new growth. Move the plant to brighter filtered light and check whether the potting mix needs replacing.

Keep Microchilus argenteus away from children and pets

• Keep this plant away from children, cats and dogs.
• Its effects after chewing or swallowing are unclear, and plant material can still cause an upset stomach.
• Contact a veterinarian or medical professional if symptoms develop or do not settle.

When was Microchilus argenteus first published, and what does it mean?

Microchilus combines Greek mikros, meaning small, with cheilos, meaning lip, referring to the orchid's labellum. The Latin epithet argenteus means silvery.

Carl Bořivoj Presl established the genus Microchilus in 1827 in Reliquiae Haenkeanae, volume 1, page 94.

José Mariano da Conceição Vellozo first described it as Ophrys argentea in 1831 in Flora Fluminensis, volume 9, plate 61. Eric C. Smidt and Mark Wayne Chase later placed it in Microchilus as Microchilus argenteus in 2021 in Botanical Journal of the Linnean Society, volume 197, page 337.