Goldfish Plant

How to care for Goldfish Plant

Light

Nematanthus gregarius performs best in bright, indirect light. A position near an east- or west-facing window is ideal. Direct summer sun will scorch the glossy leaves, whilst too little light results in poor flowering and etiolated growth. Some gentle morning sun is tolerated and can encourage more prolific blooming.

Watering

Water moderately, allowing the top centimetre of compost to dry out between waterings. Use lukewarm, room-temperature water, as cold water can shock the roots and mark the foliage. Reduce watering in winter when growth slows. Overwatering is the most common cause of plant failure, leading to root rot in the fleshy stems.

Soil and potting

Use a light, well-draining epiphytic mix that mimics the plant's natural tree-bark habitat. A combination of peat-free multipurpose compost with added perlite or coarse orchid bark works well. Good aeration around the roots is essential; heavy or compacted compost will cause waterlogging and decline.

Feeding

Feed every two weeks from spring through to early autumn using a balanced or high-potassium liquid fertiliser diluted to half strength. A high-potassium feed, such as a tomato fertiliser, applied once flowering begins can help prolong and stimulate blooming. Do not feed during winter.

Humidity and temperature

This species requires moderate to high humidity, ideally above 50 percent. In heated homes during winter, humidity often falls too low, which can cause leaf drop and bud failure. Placing the plant on a tray of damp pebbles or using a room humidifier helps. Maintain temperatures between 16 and 24 degrees Celsius. Avoid cold draughts, air-conditioning vents, and temperatures below 10 degrees Celsius, which can be fatal.

Repotting

Repot every two to three years in spring, moving up only one pot size at a time. Nematanthus gregarius prefers to be slightly root-bound, and oversized pots increase the risk of waterlogging. Hanging baskets lined with coconut coir or terracotta pots are preferable to large plastic containers. Refresh the compost at repotting time even if you return the plant to the same pot.

Pruning

Pruning is important for maintaining a bushy, compact habit and encouraging flowering. After a flush of blooms, trim back the stem tips by one-third to one-half to stimulate branching. Leggy, bare stems can be cut back hard in early spring. Remove any dead or yellowing leaves promptly to maintain plant health and appearance.

Is Goldfish Plant toxic?

Common problems

How to propagate

Stem tip cuttings

Take 8 to 10 cm tip cuttings just below a node in spring or early summer. Remove lower leaves, allow the cut end to callous briefly, then insert into a mix of perlite and peat-free compost. Cover with a clear plastic bag to retain humidity and keep at 20 to 22 degrees Celsius until rooted, which typically takes four to six weeks.

Leaf-bud cuttings

Remove a healthy leaf with a short section of stem including the node. Insert upright into a moist, gritty rooting medium and maintain warmth and humidity. This method is slower than stem cuttings but can be useful when material is limited.

Where Goldfish Plant comes from

Native to Brazil.

Story and origins

The genus name Nematanthus derives from the Greek words 'nema', meaning thread, and 'anthos', meaning flower, referring to the slender, thread-like pedicels (flower stalks) that hold the blooms away from the stems. The species epithet 'gregarius' comes from the Latin 'gregarius', meaning belonging to a flock or occurring in groups, which reflects the plant's tendency to produce flowers in clusters along its trailing stems. The common name 'Goldfish Plant' is a direct reference to the resemblance of the inflated, orange tubular flowers to small swimming goldfish.

Nematanthus gregarius was described formally within the context of the diverse Gesneriaceae family, which has long been of interest to botanical collectors working in South America. The Atlantic coastal forests of Brazil, the plant's native range, are one of the most biodiverse and threatened biomes on Earth, and many Gesneriaceae species from this region were collected and introduced to European horticulture during the nineteenth century. The Goldfish Plant rose to popularity as a houseplant during the twentieth century, particularly in North America and Western Europe, largely due to the novelty of its distinctive, brightly coloured flowers. It remains a favourite subject for hanging basket cultivation in temperate regions where outdoor growing is not possible.

Varieties to know

Nematanthus gregarius 'Variegatus'

A cultivar bearing cream and green variegated foliage alongside the characteristic orange tubular flowers.

Nematanthus 'Black Gold'

A hybrid with very dark, almost black-green foliage that provides a striking contrast to bright orange flowers.

Nematanthus 'Tropicana'

A compact hybrid with orange and yellow bicoloured flowers, popular in hanging basket cultivation.

Fun facts

• The tubular, pinched flowers of Nematanthus gregarius have evolved to be pollinated by hummingbirds in their native Brazilian forest habitat.
• Despite its trailing habit resembling many true epiphytes, Nematanthus gregarius grows naturally both as an epiphyte on tree bark and as a terrestrial plant in leaf litter on the forest floor.
• The family Gesneriaceae, to which this plant belongs, contains over 3,500 species and includes familiar houseplants such as African violets (Saintpaulia) and Cape primroses (Streptocarpus).
• Nematanthus gregarius can flower almost year-round when given adequate light, humidity, and a cool, drier winter rest period that triggers a new flush of blooms.
• The fleshy, succulent quality of its leaves and stems helps the plant retain water during dry periods, a useful adaptation for life on exposed tree branches.

Goldfish Plant FAQ