Dischidia nummularia

The coin-leaved epiphyte of tropical Asia

Robert Brown published Dischidia nummularia in 1810. The species ranges from southern China through tropical Asia and Malesia to northern Queensland. It grows on trees and can also spread over rock.

Trailing stems follow bark, branch forks and mossy crevices in wet tropical vegetation. Small round leaves line shoots exposed to frequent rain and humid canopy air. Fine roots enter shallow pockets of organic debris, where water arrives quickly and drains across the surface. The plant’s natural setting combines regular moisture with air moving freely around its stems and roots.

Care for the trailing coin leaves of Dischidia nummularia

Light

Give Dischidia nummularia strong diffuse light beside an east window or within about 1 m of a brighter south or west window. A few hours of gentle morning sun can keep stems compact once the plant is acclimated. Fierce afternoon rays through glass can tan or shrivel the small round leaves. In low light, the gaps between leaf pairs lengthen, new coins become thinner and the curtain loses density. Light should reach the top of the pot as well as the hanging ends.

Watering

Allow most of the airy medium to dry, then soak the whole root ball and drain it completely. The slightly succulent leaves buffer a short dry spell, but repeated severe drought causes puckering, yellowing and stem loss. Constant wetness is more dangerous to the fine epiphytic roots, particularly in a deep pot. Judge moisture by pot weight and a finger or wooden stick in the mix. Heat, sun, airflow, terracotta and a small basket speed drying; cool shade, plastic and decomposed medium slow it.

Substrate and roots

Use a very open epiphytic mix such as fine orchid bark and coco chips with perlite or pumice plus a small amount of coir or quality potting mix. The fine roots need scattered moisture and large air spaces, and they perform poorly in dense peat or garden soil. A shallow pot or hanging basket suits the modest root volume. Keep the crown at surface level, maintain clear drainage and flush occasionally because salts become concentrated as this dry-open mix is repeatedly watered and fed.

Temperature

A steady 19–28 °C supports growth. Keep it above about 15 °C, with particular care when the substrate is moist. Cold window glass and draughts can chill the long outer stems even if the pot remains warm. Air-conditioning may dry one side quickly, and direct heater air can shrivel hanging tips. Avoid sharp temperature changes after a thorough watering.

Humidity and airflow

Ordinary household humidity is usually sufficient for this thicker-leaved trailing species. Moderate humidity can improve rooting at nodes and keep new leaves smooth, but the root zone must still dry promptly. Give the hanging curtain open space and mild air movement. Routine misting is unnecessary and does not reach the pot; dense wet stems with poor circulation can shed leaves.

Fertilising

Use a balanced foliage fertiliser at one-quarter strength every four to six weeks during visible extension. Epiphytic roots need only light feeding. Continue at a reduced rate through winter if the plant remains warm, well lit and actively lengthening; pause when growth and water use slow. Avoid fertilising a dry root ball and rinse the mix periodically with plain water to prevent salt crust and root-tip damage.

Repotting

Repot when the fine roots densely bind the mix, water runs past a dry core, the medium breaks down or the hanging mass makes the container unstable. A slightly snug pot is normal. Move up only 2–3 cm in diameter, preferably into a shallow container, and preserve the root ball. Tease away loose decomposed particles without stripping healthy clinging roots. Choose a warm active phase so fresh roots can settle promptly.

Trailing growth and leaf care

Use a hanging pot or let the stems spill from a shelf; tying them upright is unnecessary for the natural curtain. Turn the container occasionally so light reaches all sides and keep the crown from becoming shaded by its own trails. Cut sparse or overlong stems just above a node to encourage branching, and root healthy trimmings if desired. Support a strand during rinsing, avoid pulling intertwined stems and remove only yellow or dry sections. The small leaves need no wiping.

Coin leaves: wrinkles, yellowing and drop

• Round leaves wrinkle and lose firmness: First check the mix. A dry, lightweight root ball needs a thorough soak and complete drainage; a damp pot with wrinkled leaves suggests damaged roots, so more water would make the problem worse.
• Leaves become yellow and soft: This often follows prolonged saturation in a dense mix. Remove mushy growth, inspect for dark roots and repot into a small, loose bark-rich mix if necessary.
• Several healthy-looking leaves drop after a move: Cold, a sudden light change or a severe dry spell can trigger leaf loss. Stabilise warmth and bright indirect light, then allow the plant time to produce new growth, watering only when the substrate approaches dryness.
• Small brown or cream bumps stick to the stems: Check whether they lift off and leave sticky residue; if so, scale insects are likely. Isolate the plant and use the inspection and repeat-treatment sequence in our scale guide.

Is Dischidia nummularia safe for pets?

The effects of Dischidia nummularia on cats and dogs are unknown. Its stems release white latex when damaged, so keep it away from chewers and rinse sap promptly from skin or eyes. Contact a veterinarian if exposure causes vomiting, mouth irritation or other symptoms.

The coin-like species name

Robert Brown established both Dischidia and Dischidia nummularia in Prodromus Florae Novae Hollandiae in 1810. The genus name combines Greek words meaning “twice” and “split,” a reference to the divided staminal corona. Nummularia comes from the Latin nummulus, a small coin, and means coin-like. Brown described the species directly in Dischidia, so there is no earlier name in another genus.