Black velvet alocasia (Alocasia reginula) care

Aroids · fussy to keep

Black velvet alocasia (Alocasia reginula) wants bright indirect light, as much as it can get without direct sun. Water it every 8 days. Water when the top third dries, and never leave the pot standing in a saucer of water. Alocasias also drip water from their leaf tips in the morning — that is guttation, and it means the roots are working, not that anything is wrong. Pot it in chunky and fast-draining: bark, perlite, a little coir. Balanced feed at half strength every second or third watering, spring through summer only, and repot once a year. Humidity: above 70%. Toxic to cats, dogs and people if chewed — the sap carries insoluble calcium oxalate crystals, which burn the mouth and throat.

Black velvet alocasia: small, low and matte black, with silver veins, and a texture like felt. It is a rheophyte from stream banks in Borneo and wants a very open mix and genuinely humid air. The smallest alocasia here and the one most often lost to a wet pot.

Quick facts

Water: Water every 8 days. Water when the top third dries, and never leave the pot standing in a saucer of water. Alocasias also drip water from their leaf tips in the morning — that is guttation, and it means the roots are working, not that anything is wrong.
Light: Bright indirect light, as much as it can get without direct sun.
Humidity: Above 70%.
Soil: Chunky and fast-draining: bark, perlite, a little coir.
Feeding: Balanced feed at half strength every second or third watering, spring through summer only.
Repotting: Repot once a year.
Toxic to pets: Toxic to cats, dogs and people if chewed — the sap carries insoluble calcium oxalate crystals, which burn the mouth and throat. Keep it off the floor if anything in the house tastes its way through life.
Difficulty: Fussy.
Mature size: 25–40 cm tall.
Native to: Borneo.

Watering a Black velvet alocasia

Water every 8 days. Water when the top third dries, and never leave the pot standing in a saucer of water. Alocasias also drip water from their leaf tips in the morning — that is guttation, and it means the roots are working, not that anything is wrong.

That cadence is the one PlantParlour sets for this species when you name it, and it is deliberately on the cautious side — a plant that asks a day early is safer than one that asks a day late. Log each watering and the reminder moves with the plant rather than with the calendar.

Light

Bright indirect light — more than people give them. An alocasia in a dim room loses a leaf for every new one it makes and slowly winds down to nothing. Direct afternoon sun, though, burns holes in those thin leaves.

Humidity and temperature

Above 70%. Central heating in winter is what turns a comfortable room into a dry one, and it is the usual reason an established plant suddenly browns at the edges or picks up spider mites.

Soil and potting

Alocasias grow from a corm, and a corm sitting in wet compost rots. Use a very open mix and a pot with real drainage. Many growers keep them in semi-hydroponics for exactly this reason.

Feeding

Balanced feed at half strength every second or third watering, spring through summer only. Stop feeding in autumn and start again when you see new growth in spring — feeding a plant that isn't growing just builds up salts in the pot.

Repotting

Repot once a year. Once a year in spring. Expect to find offsets — small corms around the parent — which can be potted separately. Do not size up more than one pot at a time.

Common problems

Leaves dropping one after another over winter
Dormancy. Alocasias often go down to nothing and come back in spring.

Fix: Cut the water right back, keep the corm just barely damp, stop feeding, and wait. Throwing it out in February is the usual mistake.
Fine webbing, leaves going dull and stippled
Spider mites. This genus is their favourite.

Fix: Shower the plant, wipe both sides of every leaf, and treat weekly for a month. Raise the humidity or they come straight back.
Yellow leaf with a brown mushy stem
Rot at the corm from a wet mix.

Fix: Unpot immediately, cut back to firm white tissue, and repot into bark and perlite.
Dry brown patches in the middle of a leaf
Sunburn.

Fix: Move it out of direct sun; the damage does not heal.

Propagation

Separate the offsets at repotting. Each corm, even a bare one the size of a hazelnut, will sprout in damp sphagnum in a covered box over a few weeks.

A cutting taken in PlantParlour keeps its link to the plant it came from, so a propagation years later still traces back to the mother plant — which is the point if you ever sell or trade it.

Toxicity and safety

Toxic to cats, dogs and people if chewed — the sap carries insoluble calcium oxalate crystals, which burn the mouth and throat. Keep it off the floor if anything in the house tastes its way through life.

Questions people ask

How often should you water a Black velvet alocasia?

Water every 8 days as a starting point — that is the cadence PlantParlour sets for Alocasia reginula. Water when the top third dries, and never leave the pot standing in a saucer of water. Alocasias also drip water from their leaf tips in the morning — that is guttation, and it means the roots are working, not that anything is wrong. Light, pot size and the time of year all move that number, so treat it as a reminder to go and check rather than a rule.

How much light does a Black velvet alocasia need?

Is Black velvet alocasia toxic to cats and dogs?

How do you propagate a Black velvet alocasia?