Alocasia

Around ninety species of bold-leaved aroids from tropical Asia, grown for arrow- and shield-shaped leaves that can be glossy, veined or velvet. They share one care rhythm and one habit that surprises new growers: a winter rest. This guide covers the genus; standout species and cultivars get their own cards.

Care at a glance

Origin & history

One rhythm across the genus. Alocasia is a genus of roughly ninety aroids native to tropical and subtropical Asia, from India and southern China through Southeast Asia to New Guinea and northern Australia (Plants of the World Online, n.d.). They grow from a fleshy corm or rhizome, a swollen underground stem that stores energy, and push up large arrow- or shield-shaped leaves on tall stalks.

Because they evolved to warm, humid forest floors and clearings, the whole genus wants the same things indoors: bright indirect light, steady warmth, a chunky mix that drains fast, and humidity most homes have to raise on purpose. Give them that and they grow quickly through the warm months.

What differs between species is mostly the leaf: glossy and green, deeply lobed, veined silver, or thick and velvet. Those differences, and the few that change care, live on the species cards in this guide.

Care in depth

Light and warmth. Bright, indirect light is the target; direct midday sun scorches most Alocasia, and deep shade stalls them. Keep them warm, roughly 65 to 80°F (18–27°C), above about 60°F (16°C) while growing and never below 50°F (10°C). They dislike cold drafts and sudden chills.

Water and humidity. Through the growing season, water when the top inch or two of mix is dry, then let the excess drain; the roots rot in soggy mix. Humidity is where most people come unstuck: Alocasia want it high, ideally 60 percent or more, and dry air brings brown, crisp edges and invites spider mites. A humidifier does more than misting.

Substrate and nutrients. Pot in a chunky, airy aroid mix built on bark and perlite so water runs through quickly. Feed a balanced fertilizer at half strength through spring and summer, and stop once growth slows for the year.

Common problems & pests

What you see	Likely cause	What to do
Fine webbing, pale stippling	Spider mites (dry air)	Rinse; raise humidity; insecticidal soap.
Brown, crisp leaf edges	Low humidity	Raise humidity; a humidifier beats misting.
Yellowing, then leaf drop in winter	Onset of dormancy	Normal; cut water back, keep the corm warm.
Yellowing with soft, mushy base	Overwatering or rot	Let it dry; chunkier mix; check the corm.
Drooping despite moist soil	Cold or root stress	Warm it up; ease off water; check drainage.

In this genus

Each plant inherits the genus care above; the note is only what differs. Photos to come.