Alocasia Infernalis (Black Magic jewel alocasia) care

Light

In the wild alocasia infernalis grows on the bright edge of a forest canopy, not in the canopy and not in the open. Indoors, that translates to within a metre of an unobstructed window, sheer curtain optional. Bright, indirect light brings out the iridescent dark sheen; too little and the leaves dull and growth slows. Avoid direct sun, which scorches the foliage. Filtered light or a grow light in a cabinet works well. The fastest test: a hand held at the leaf casts a soft-edged shadow at noon — sharp shadow means too much sun, no shadow means too little light.

Watering

Aim for when the top 2-3 cm of medium is dry, roughly every 5-7 days for alocasia infernalis, but treat that as a starting point rather than a rule. A south-facing summer windowsill will dry the pot twice as fast as a north-facing winter room. Lift the pot; if it feels noticeably lighter than it did wet, water it. Keep lightly moist but never soggy; the small corm rots quickly in cold, wet conditions. Let the surface dry between waterings and reduce in winter. Many growers favour semi-hydro for steadier moisture control.

Soil and pot

Alocasia Infernalis grows best in very airy aroid mix or semi-hydro. Use a chunky blend heavy on perlite, bark, pumice, and charcoal, or grow in LECA. Maximum aeration around the corm is the single most important factor in keeping this rot-prone jewel alive. A pot with a working drainage hole is non-negotiable for this species — even free-draining mix will turn soggy in a closed planter. If you love the look of a decorative pot without a hole, use it as a cachepot around an inner nursery pot you can lift out to water.

Humidity and temperature

Alocasia Infernalis sits happiest at around 70-90% humidity and 20-29°C (68-85°F). Needs consistently high humidity and is happiest in a terrarium or cabinet. Below 60% it sulks and the leaf edges brown. Provide stable humidity with gentle airflow to prevent fungal issues. If you keep the room above 20 year-round and avoid placing the plant near a cold draught, a hot radiator, or an air-conditioning vent, you have already handled the two biggest indoor stressors.

Fertilising

Feed alocasia infernalis sparingly. Feed every 3-4 weeks in active growth with a dilute balanced fertiliser at quarter to half strength, or a hydroponic nutrient if in LECA. The small root system burns easily, so keep feeds weak and stop in winter. Skip fertiliser entirely on a stressed, recently-repotted, or actively wilting plant — fertiliser salts make damage worse, not better. Wait for a round of healthy new growth before resuming a feeding rhythm.

Common problems

Below are the issues we see most often on alocasia infernalis in the Growli community. Each is annotated with the most common cause so you know where to start.

• Corm and root rot — Soggy or dense medium quickly rots the small corm. Use an airy mix or semi-hydro and let it dry between waterings.
• Dull, faded leaves — Too little light mutes the metallic sheen. Increase bright indirect light or add a grow light, avoiding direct sun.
• Browning edges / sulking — Low humidity stresses this jewel species. Keep humidity above 70%, ideally in a cabinet.
• Spider mites — Dry air encourages them; inspect undersides and crevices. Rinse and treat with insecticidal soap or neem.

Propagation

Propagate by separating offsets or corms when repotting. Detach a firm corm, set it in moist airy medium or LECA, and keep warm and very humid until it shoots; growth is slow, so be patient. Propagation is the cheapest, most satisfying way to expand a collection — and it doubles as insurance against losing a mature plant to an accident. Take a backup cutting once the parent is established and healthy.

Toxicity to pets

Alocasia Infernalis is toxic to pets. ASPCA lists Alocasia as toxic to cats and dogs. Alocasia infernalis contains insoluble calcium oxalate crystals; chewing causes oral burning, profuse drooling, vomiting, and swelling of the mouth and throat. Keep away from pets. If you keep cats, dogs, or curious children in the house, weigh placement carefully — a high shelf or a hanging planter is enough for casual safety. For severe ingestion incidents, call your local vet and the ASPCA Animal Poison Control Center (in the US, 888-426-4435).

Pet-safety status is sourced from the ASPCA Toxic and Non-Toxic Plant List, which catalogues the most-asked-about plants for cats, dogs, and horses.

Alocasia Infernalis deep-dive guides

Every aspect of alocasia infernalis care, each with its own calibrated guide:

• Alocasia Infernalis watering schedule
• Alocasia Infernalis light requirements
• Best soil mix for alocasia infernalis
• Alocasia Infernalis fertilizing guide
• When to repot alocasia infernalis
• How to propagate alocasia infernalis
• Alocasia Infernalis growth rate & size
• Alocasia Infernalis cold hardiness
• Alocasia Infernalis temperature & humidity
• Is alocasia infernalis toxic to cats & dogs?
• Is alocasia infernalis toxic to cats?
• Is alocasia infernalis toxic to dogs?

Featured in these plant shortlists

Alocasia Infernalis qualifies for 4 curated Growli shortlists — each one filtered objectively from our structured plant-care library, so the selection is consistent and checkable:

• Best plants for a north-facing window — Houseplants for a north-facing window: bright, even, indirect light and no scorching direct sun. Each pick verified against its documented light needs.
• Best humidity-loving houseplants — Houseplants that thrive in a bathroom, kitchen, or by a humidifier — selected by documented humidity preference.
• Houseplants toxic to cats & dogs — The common houseplants the ASPCA lists as toxic to cats and dogs — the ones to keep out of reach, each with its symptoms and a safe alternative.
• Best small & tabletop houseplants — Compact houseplants that stay under about 40 cm — desk, shelf and windowsill plants that never outgrow a small space.
• Browse all 29 plant shortlists — pet-safe, low-light, drought-tolerant and more

Related guides

Alocasia Infernalis is also commonly called Black Magic jewel alocasia or infernal alocasia.

• Types of alocasia — varieties identified, with care and pet-safety
• Monstera care — light, water and common problems
• Pothos care — light, water and common problems
• Fiddle leaf fig care — light, water and common problems
• All 2464 plant care guides in the Growli library