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Goldfish plant

Nematanthus gregarius, Gesneriaceae

Sources last read 14 September 2026.

Middling It gives warning, with time to act.

Also called Candycorn Plant, Clog Plant, Gold-Fish Plant and Hypocyrta.

Goldfish plant (Nematanthus gregarius), the whole plant.
Daderot, CC0 · Wikimedia Commons

Toxicity is partly unassessed

  • Not assessed for cats. This plant is not on the ASPCA list. That is not a finding of safety: none of the sources read for this site gives an answer either way. Treat it as unknown.
  • Not assessed for dogs. This plant is not on the ASPCA list. That is not a finding of safety: none of the sources read for this site gives an answer either way. Treat it as unknown.
  • Not assessed for people. RHS publishes no harm statement for this plant. That is not a finding of safety: none of the sources read for this site gives an answer either way. Treat it as unknown.

What the sources say about its care

Light
Partial shade
RHS · read 13 September 2026
Water
Moist but well-drained
RHS · read 13 September 2026
Humidity

No source read publishes a humidity figure for any plant on this site. What follows is general guidance for foliage plants.

ASHRAE recommends indoor relative humidity between 30% and 60% 30–60%
Penn State Extension · read 13 September 2026
Temperature

How cold this tolerates, not what it prefers. No source read for this site publishes a preferred range for a plant indoors.

H1B — 10–15°C 10–15 °C
RHS · read 13 September 2026
Soil
Loam, Sand; pH Acid or Neutral
RHS · read 13 September 2026
Toxic to cats
Not on the ASPCA list. That is not a finding of safety.
ASPCA · read 13 September 2026
Toxic to dogs
Not on the ASPCA list. That is not a finding of safety.
ASPCA · read 13 September 2026
Harmful to people
No statement of harm to people is published for this plant; that absence is not evidence it is safe.
RHS · read 13 September 2026

How it usually goes wrong

Crisp margins that appear in winter

The goldfish plant shows browning on many leaves at once, all at the margin, with no spots or soft patches anywhere.

Leaf margins are the end of the water supply, so they are the first tissue to run short when the air takes more than the roots can send. Penn State Extension cites 30% to 60% as the recommended indoor range, and a heated room in winter sits below it.

Telling it apart: Whether the damage advances. Dry air marks a leaf and stops; rot keeps going.

Penn State ExtensionDiagnose brown tips and edges on this Goldfish plant
Flowering stops while the foliage carries on

The goldfish plant looks well in every other respect: green, firm and growing. What is missing is the flowering.

Buds are formed only when the plant has energy to spare. Its source places it in partial shade, and in less light than that the surplus that pays for flowers is missing.

Telling it apart: The rest of the plant. A healthy, leafy plant without flowers is short of light or of a season it needs; a plant that is also yellowing has a root or water problem first.

RHSDiagnose no flowers or dropped buds on this Goldfish plant
Pale, undersized leaves at the tips of the stems

Older leaves on the goldfish plant keep their colour while each new one comes in thinner, with a longer stretch of bare stem below it.

Placed darker than the partial shade its source describes, the plant invests in length rather than leaf, because length is what finds a window.

Telling it apart: What the newest growth looks like beside the oldest. Light changes what arrives next; feeding changes what is already on the plant.

RHSGoldfish plant leaves turning yellow: causes
The older part of the plant yellows while the compost stays soaked

The goldfish plant yellows from the base up. Affected leaves bend rather than snap, and the pot is still heavy several days after watering.

Water held around the roots for days leaves them without air, and a root without air stops working within a week. Its source describes moist but well-drained soil for good reason.

Telling it apart: Lift it from the pot. Firm pale roots mean the water is not the problem; brown soft ones that smell sour mean it is.

RHSGoldfish plant leaves turning yellow: causes

Not sure which it is? Ask the diagnosis questions for Goldfish plant.

Routine care

Watering
As a houseplant, give it bright, filtered light, a peat-free potting compost, and soft water.
NC State Extension · read 13 September 2026
Keep under glass, or grow indoors as a houseplant, using peat-free potting compost; give bright, filtered light and water with soft water.
RHS · read 13 September 2026
Propagation
Root cuttings, stem cuttings
NC State Extension · read 13 September 2026
In spring, root softwood (stem-tip) cuttings.
RHS · read 13 September 2026
Pruning
Pruning is not needed, but pinch shoot tips on young plants to promote branching.
RHS · read 13 September 2026
Pests and diseases
Young growth in particular can attract aphids. Diseases: usually none.
RHS · read 13 September 2026

Move something and watch

Loading the simulator. It needs JavaScript; the care table above does not.

About the plant

Nematanthus gregarius, also called the clog plant or goldfish plant, is a species of flowering plant from Brazil in the gesneriad family, Gesneriaceae, making it a relative of such genera as Streptocarpus and Aeschynanthus.

From Wikipedia, CC BY-SA 4.0 · read 13 September 2026

Native range
SE. Brazil
World Checklist of Vascular Plants, June 2026 release, CC BY.
Kew WCVP · read 13 September 2026
Brazil
NC State Extension · read 13 September 2026
Brazil
RHS · read 13 September 2026
Climate
wet tropical
World Checklist of Vascular Plants, June 2026 release, CC BY.
Kew WCVP · read 13 September 2026
Growth form
epiphyte
World Checklist of Vascular Plants, June 2026 release, CC BY.
Kew WCVP · read 13 September 2026
Epiphyte, Perennial, Shrub; habit creeping
NC State Extension · read 13 September 2026
Trailing (evergreen)
RHS · read 13 September 2026
Size
Height up to 18 in; width up to 39 in
NC State Extension · read 13 September 2026
Height 0.1-0.5 metres; spread 0.5-1 metres after 2–5 years
RHS · read 13 September 2026
Flowering
Flowers orange; blooms in summer
NC State Extension · read 13 September 2026
Flowers orange in summer
RHS · read 13 September 2026

Common problems with Goldfish plant

More of the Gesneriaceae family

Plants with similar care

Sources

What this does not cover

The figures above are what published sources say, not measurements of the plant in your room. They say nothing about your pot size, your water, the season, or how far from the glass the plant stands, and those decide more than any figure here does.

Humidity has no species figure because no source read for this site publishes one, and the only temperature published for this plant is a cold floor. The simulator fills those gaps with general figures for its kind of plant, marked as general and listed on how we read sources. Where a toxicity row says the plant was not assessed, that is the absence of a finding and not a finding of safety.

If something is already wrong, the diagnosis tool asks about the soil, the window and the watering, which is where the answer usually is.