Stop Trying to Keep Elephant Ear as a Houseplant
Horticulturist extends this one humble plea. But, if you’re going to do it...
With those large, heart-shaped, wonderfully dramatic leaves, it’s no wonder why so many people try bringing Colocasia into their living space.
Keyword? Try.
A family of towering tropical perennial plants native to Southeast Asia, Colocasia, or Elephant Ear, can be grown outdoors in warm, humid regions with great success. Indoors, it tends to face more issues, as plant parents can't replicate (or even get close) to its favored conditions.
Let’s get one thing straight: horticulturist Timothy Heslop does not condone keeping Colocasia as a houseplant. But, should you have already taken the plunge — or if you’re feeling rebellious — here’s some background on your tropical beauty, and advice for keeping it as happy/alive as possible.
Question: Can you elaborate on why Elephant Ear isn’t what we might call an “ideal houseplant”?
Timothy Heslop: Colocasias are most often used outdoors as focal points in container gardens or in the ground to add a bold texture to the garden in the warmer months. They thrive in the warm, humid weather and bright natural light of summer and can quickly decline when brought indoors. The biggest factor in keeping these plants healthy indoors is maintaining the high light and humidity they thrive on. In most scenarios, bringing your colocasia into a typical home can lead toleaf dieback, weak new growth, and several pest problems (most notably spider mites).
Q: Why are these plants prone to more problems than other tropical natives?
TH: Colocasias are particularly susceptible because of their most beautiful feature: their gloriously big leaves. Colocasia leaves are thin and their petioles (leaf stem) are very soft and fleshy in nature, making them particularly weak when not grown in ideal circumstances.
Q: Got it. For those who might have already taken the plunge, can you share your recommendations for growing Colocasia indoors?
TH: First, watering this plant will change dramatically indoors. When grown outside, Colocasias love moisture and can even thrive in completely saturated soil (some species grow as semi-aquatic plants). Indoors, however, their fleshy stems and roots will quickly rot in saturated soil. They actually prefer to stay on the dryer side, allowing the soil to dry several inches down from the top before watering again. The best practice for these guys is to water lightly and regularly.
The main factor in this dramatic change is light. When the Colocasia is in bright, uninterrupted light, it is constantly transpiring (sweating, essentially), expelling the moisture it soaks up from the soil as water vapor. When we bring the plant indoors and reduce that light level, those thick absorbent roots are stuck holding onto water they would normally send upward to support their sun-drenched leaves. As a result, they become susceptible to fungi and bacteria in the soil.
For this reason, it is also important to not fertilize your colocasia as heavily as you would outdoors. Encouraging lots of growth indoors can lead to long, spindly stems with weak leaves and you’ll lose that great Colocasia character.
You can expect your oldest leaves to discolor and turn yellow or brown over time, but this is just the plant shedding leaves that were meant for its old environment. As long as your newest leaves are a healthy green, you should be good, and these older leaves can be cut off as they decline.
Q: What about keeping Colocasia as an outdoor plant? How should one approach caring for it in the winter?
TH: If you are able to grow your Colocasia outdoors in the warm months (when night temperatures are above 55F) then a good alternative is storage. Most of these plants are grown from large tubers called corms, which can be allowed to go dormant and stored during the dry or winter months.
The best way to store a Colocasia is to start sooner than one might think.
Stop fertilizing these plants mid to late summerto help signal the end of the growing season and slow growth. When the night temperatures start to fall below 55 degrees, this is the best time to dig up your plant and prepare it for storage. A little cool weather at the end of the growing season is beneficial in telling the plant it's time to stop growing, and most Colocasias can even survive a light frost, but it’s best not to push its limits.
After you have dug up your Colocasia, you want to cut all of the leaves off, leaving four to six inches of stemleft at the base of the plant. You can leave the roots intact and place in a pot to be stored in a cool, dark space, or wash the soil off the plant entirely and allow it to dry completely, leaving just the corm.
I would recommend leaving the root ball intact over the winter and allowing the soil to dry almost completely, watering lightly once every four to six weeks. When allowed to go completely dormant, drying down to the corm, these plants take quite a while to get started again in the spring. When storing, expect to have a little growth occur, small new leaves stretching up from the center. It is best to cut these leaves off as they come out to help keep the plant’s energy reserves in the corm, ready for next season.
Q: Are there other plants you’d suggest for someone who loves the look of a Colocasia?
TH: Unfortunately, there is no houseplant that can provide a comparable look to the Colocasia, but some bold-leafed alternatives are Monstera, Anthurium, Birds of Paradise, as well as some large Philodendrons and Alocasia.