Dioscorea amaranthoides (metallic form)

A metallic-leaved South American yam

Dioscorea amaranthoides is a South American yam species. The name var. metallica was formally published for metallic-looking plants but is now treated as a synonym, not an accepted botanical variety. In current taxonomy the plant remains D. amaranthoides.

The species ranges from Colombia across tropical South America to central Brazil and northeastern Argentina. It is a tuberous climber from seasonally dry tropical vegetation. Slender stems wind through surrounding plants and carry the leaves into brighter openings, while an underground storage organ holds reserves through seasonal change. This South American climbing habit provides the natural background for the metallic form.

Care for a caudex through growth and rest

Humidity and airflow

Normal household humidity is workable if watering is steady. Give the vine gentle airflow through its support and ensure the caudex or substrate surface dries after watering.

Light

Place the vine close to an east-facing window or a short distance from a brighter south or west window with the fiercest sun filtered. In weak light, the vine searches, spaces its leaves widely and loses colour contrast; move the support closer to the light without roasting an exposed caudex or tuber.

Watering

Let the live vine determine watering. During active leaf growth, water when the upper layer of the substrate has dried but before the rooted core becomes dry, soaking the pot and draining it completely.

Root care

Heater air can dehydrate young leaves before the roots replace the loss.

Fertilising

Feed Dioscorea amaranthoides only while the vine is leafy and actively lengthening, using a dilute balanced fertiliser. Stop once yellowing shows that its growth cycle is ending.

Repotting

Repot when roots circle the drainage zone, the storage organ presses against the container, the mix collapses or watering becomes erratic. The safest point is just as a new growth cycle begins.

When Dioscorea amaranthoides (metallic form) needs attention

• New leaves show a bronze or metallic cast: The reflective bronze sheen is normal for this form, especially on young foliage. Pest damage appears as irregular stippling, dustiness or scars, while the natural metallic sheen is even across firm tissue.
• Fast-growing stems tangle or collapse: This is a climbing vine and needs support early. Guide flexible new stems around a trellis without forcing sharp bends; untangle them patiently and leave the underground rootstock undisturbed.
• The vine yellows and dies back while the base remains firm: This can be its normal seasonal rest. Reduce water as foliage declines and keep the underground rootstock only barely moist until growth resumes; softness, dark wet tissue or a sour smell is consistent with active rot instead. Our dormancy guide helps tell the two apart.
• Fine pale dots spread across the elongated leaves: Inspect beneath the blades and along the vine for spider mites. Keep the plant apart from others, rinse it thoroughly and make follow-up applications, taking care not to snap the long stems.

Keep Dioscorea amaranthoides (metallic form) 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.

Dioscorea amaranthoides: where the name comes from

Dioscorea commemorates the Greek physician and botanist Pedanius Dioscorides. The epithet amaranthoides means resembling Amaranthus.

Carl Linnaeus established the genus Dioscorea in 1753 in Species Plantarum, page 1032; Charles Plumier had proposed the name.

Carl Bořivoj Presl first described Dioscorea amaranthoides in 1827 in Reliquiae Haenkeanae, volume 1, page 134.