Alocasia: the misunderstood houseplant
Updated: Jun 12, 2020
One of the most rewarding houseplants, for me, are alocasias. When they unfurl a new leaf it takes your breath away and makes you feel like the proudest plant parent ever. They make great specimen plants, and also look great in a plant gang.
But, a lot of people misunderstand alocasias' needs. In fact, we get a lot of people coming into the shop asking why their alocasia is dying. Most plant retailers don't explain how to look after plants, so a lot of people rely on google and boy can that give you some bad advice! Most online articles about alocasias tell you to keep the compost moist at all times, and never to give them direct sunlight. Phooey! Following this advice will result in a waterlogged plant and eventually, root rot.
Alocasias do need lots of water, but they also need to get lots of oxygen around their roots. To achieve this, they need bright light, which helps them use the water in the pot quickly, so that it dries out and lets air in. I was perplexed when I saw big alocasias in the reptile house at Bristol Zoo, growing under a waterfall. They appear to like running water, but stagnant water sitting in a pot is a big no-no.
My Alocasia cucullata gets bright light all day, with a few hours of direct sun in the morning. My Alocasia zebrina gets bright light all day, with an hour of direct sun in the late afternoon. When people ask me about their unhappy alocasia, I always recommend more light and less frequent watering, and it always works.
So here's the lowdown for a happy alocasia:
- Let at least the top 2 inches of compost dry out before watering.
- Give your alocasia a bright spot. A sun-trained alocasia can enjoy several hours of direct sun each day.
- Alocasias are heavy feeders in the growing season, so feed them fortnightly over spring and summer.
- Wipe the leaves regularly or give your alocasia a shower. This will help avoid infestations of spider mite, which like warm, dry conditions.
- Alocasias prefer humid conditions, so avoid radiators! A bright bathroom is the perfect spot.
- Aerate the soil occasionally. See my blogpost ‘Be the Worm’.
- Alocasias are cold sensitive, so keep them in a warm spot over winter. No cold draughts or cold windowsills.
- Remember, all members of the Araceae (Arum) family contain oxalate which makes them toxic to animals.