Caladiums have large colorful leaves that are very striking. They are tropical plant that prefers a humid climate. Today, I will explain issues that can occur with the leaves and how to get them your caladium back to full health.
Over or underwatering, the wrong soil pH, too much sun and wind, pests, and the wrong temperature can cause caladium leaves to curl. To make caladium return to normal only water when the soil is dry, treat pests with neem oil, ensure the soil has a pH of 6.0 to 6.5, and keep leaves out of direct sunlight.
Overall, leaves curling is a sign that the caladium plant is under stress. The way the leaves are curling gives a good indication as to what is causing the leaves to curl. Here’s a quick list for reference:
- Curling down – underwatering
- Curling up – heat, sun, or wind stress
- Curling with yellowing of the leaves – overwatering
I’ll explain how to remedy each of these issues as well as the other symptoms of each of the issues so that the leaves of your caladium can be rigid, flat, and beautiful.
Too much sunlight causing the leaves to curl up
Leaves curling up is a defense mechanism that protects the leaves from excess sunlight, as well as from the wind. Caladium do not like direct sunlight for extended periods, and most can only take a small amount of direct sunlight in the early morning and late at night.
This goes double for varieties of caladium that have transparent leaves. The leaves curling up block the sunlight and wind from damaging the top of the leaves.
- Move your caladium where they will get bright light but not direct sunlight.
- Experiment with giving them 1 hour of sunlight in the morning and evening and see how they respond.
Not enough water causing leaves to curl under and drooping stems
If the soil is kept too dry for too long caladiums can begin to collapse from exhaustion. The stems can bend rather than being straight up and rigid. The leaves will begin to curl under as they don’t have enough water in the plant to keep them rigid. Once this is resolved within 5 minutes or so the leaves and stems will be back to normal.
- Soak the soil allowing water to drain out of the bottom of the pot.
- Regularly test the soil with a finger to feel how dry it is, and water when it’s dry to the touch.
Soil that isn’t free draining or the wrong pH
Caladium needs free-draining soil that is the consistency of the potting mix. If they’re planting in soil that is too sandy or too clayey they can struggle to uptake nutrients which causes the leaves to begin to curl.
The pH of the soil controls what nutrients are available in the soil due to the chemical reactions that take place. The pH of the soil can be tested using an inexpensive soil testing kit. Ideally, the soil should have a pH of 6.0 to 6.5. But, provided potting mix is used the pH should be within this range.
- Replant them in soil that has the consistency of the potting mix.
- Ensure the holes at the bottom of the pot are not blocked.
The temperature is too warm or too cool
Caladium is native to tropical regions of South America. Because of that they do best in temperate climates and thrive in tropical-like conditions. In very cold weather, or extremely dry weather they can really struggle which will show in the curling of the leaves.
This type of curling generally occurs before the leaves become crispy, dry, and brown in the case of conditions that are too dry. Or, will have stunted growth which can cause the soil to be overfertilized. Which in turn causes the leave to curl and show yellow spots. These yellow spots are distinct from the natural colors of the leaves, which can also be yellow.
- For daytime temperatures keep them at about room temperature, 70 °F (21 °C).
- Don’t keep them where the temperature will go below 60 °F (15 °C).
- Keep them where the humidity is above 50%.
Watering the soil too often making the soil waterlogged
Although caladium is used to humid environments if the soil is waterlogged rather than damp the roots can begin to rot. This causes them to be less effective at drawing up moisture. Which results in the caladium being deprived of nutrients and water.
The lack of nutrients shows as yellow spotting on the leaves. And the leaves can curl and shows browning on the edges.
- When watering completely wet the soil profile but allow the water to drain out from the bottom completely.
- Keep the holes at the bottom of the pot free so that water can easily pour out.
- Don’t allow water to pool in the drip tray for more than a day.
Pest insects eating the leaves causing them to curl as they die
Indoor caladium generally isn’t prone to insects but they can get infested from time to time. They are visible on the stems and leaves. Especially on the underside where they like to hide. Common insects are scale, mealybugs, and aphids.
This will bite into the leaves and stem and suck out the nutrients. Mealybugs live on the underside of the leaves. And the tops of the leaves will have a bite mark surrounded by a dead area. As the leaves are deprived of nutrients the leaves can curl, turn brown, and drop off.
Pest insects are generally fine but their numbers can get out of control to the point where they will kill the plant.
Any insecticide or neem oil are effective at killing them completely. Rubbing alcohol also called isopropyl alcohol or methylated spirits is also very effective and killing them.
- Spray the entire plant with neem oil or an insecticide after sunset.
- Alternatively, dab the insects with a cotton bud soaked in isopropyl alcohol.