Some houseplants aren’t picky about temperature or humidity and thrive in almost any indoor environment. Calathea is not one of these plants, instead preferring a specific range of temperature and humidity conditions. Even temporary variations in the desired humidity level for this plant can lead to color loss and leaf drop. They’re less sensitive to temperature but still have a definite preferred range. Learn how to keep your Calathea happy with the perfect conditions.
- Calathea Plant Temperature and Humidity Tolerances – The Essentials
- Typical Temperature and Humidity Ranges for Calathea Plants in Their Native Habitat
- Signs Your Calathea Plant Isn’t in the Right the Temperature and Humidity Level
- Ideal Temperature and Humidity Conditions for Calathea Plants
- How to Boost Humidity in Your Home
- Caring for Calathea Plants in Spring and Summer
- Caring for Calathea Plants in the Winter
- Wrapping Up Calathea Plant Temperature & Humidity Requirements
Calathea Plant Temperature and Humidity Tolerances – The Essentials
Calathea needs to stay warm at an ideal temperature of 68 to 82 degrees F. Cold drafts and dips in temperature can cause leaf drop or discoloration. For humidity, higher is better for Calatheas. They thrive in nearly 100% humidity environments, so any humid air you can offer will help.
Typical Temperature and Humidity Ranges for Calathea Plants in Their Native Habitat
In their native habitats, Calathea plants are exposed to high humidity and warm temperatures nearly year-round.
They’re found in the tropical parts of South and Central America. Brazil is home to multiple Calathea species that are popular as houseplants throughout the rest of the world.
Calatheas typically grow at the base of mature trees in the jungles of tropical regions. These plants receive little light and plenty of moisture and humidity. Wintertime temperatures are mild in these areas, so Calathea varieties can’t handle frost or anything near-freezing temperatures.
Even colder indoor rooms can shock them and stunt their growth, especially in winter. The key is to mimic the natural environment they’re used to in the jungle, including in humidity and warmth. This may require some special equipment, even though the Calathea rarely needs specialty supplemental light.
These plants often grow at temperatures between 85 and 95 degrees F in the daytime and 75 to 85 degrees at night. Relative humidity remains nearly 100% all year round in much of the jungle.
Thankfully, you don’t need to mimic these intense conditions inside your home perfectly. Getting close to the temperature and humidity levels will go a long way in encouraging good Calathea growth.
Signs Your Calathea Plant Isn’t in the Right the Temperature and Humidity Level
Calathea plants are sensitive to humidity and temperature fluctuations. While too much light, poorly draining soil, too little water, or lack of nutrients can also interfere with good growth or color from these plants, they’re both problems that are relatively easily solved. Common signs of temperature issues include:
- Limp or drooping leaves, a problem also caused by overwatering or under watering
- Loss of color or pattern, especially if leaves darken rather than turn light-colored
- Slow growth and a lack of new leaves
- Leaf drop if the temperature drop is severe or extended in length.
When the problem is a lack of humidity instead, Calathea plants exhibit problems like:
- Crispy brown edges on older leaves, which indicate both under-watering and a lack of moisture in the air
- Wilted leaves that don’t perk up from temperature improvements (see our guide to pruning calathea plants for more).
- Rapid drying of soil between watering, making it hard to maintain a proper level of moisture
- Slow growth
- Pale leaves with a lack of color or pattern.
Excessive humidity is rarely a problem for Calathea, but it can lead to dark spots on the leaves or grey mold growth around the stems. After adjusting humidity levels, simply water less and avoid misting for a while to encourage the plant to dry out a little.
Inappropriate temperature and humidity can also attract common Calathea plant pests and diseases.
Ideal Temperature and Humidity Conditions for Calathea Plants
You might not be able to turn your home into a jungle just to make Calathea plants happy. But you’ll need to find a way to control both the temperature and humidity level around the plant since it’s hard to keep the entire home as warm and humid as necessary.
Start by keeping the plant away from any sources of cold air or drafts. Don’t place it near doors or winters in the winter, and avoid air conditioning vents in the summer. While placing the Calathea near a heating vent may keep it warm, it will also dry out the air around the foliage. You’ll have to compensate with extra humidity if you have to add any heating since it tends to dry the plant out.
Use a reliable humidity monitor set near the Calathea to check when to mist or add additional humidity. Small temperature and humidity meters are easy to find at any hardware or home supply store.
Misting will raise the ambient humidity around the plant only a few degrees. Try a small humidifier set next to the plant for a more significant boost of humidity. This ensures a pocket of high humidity just for the plant without making the rest of the house too damp.
Locate the Calathea near indirect light sources like North or East facing windows, so they don’t dry out too quickly.
A bathroom or even a laundry room may be a good choice for this type of house plant since it needs little light and enjoys the humidity of these rooms.
How to Boost Humidity in Your Home
Without reasonable humidity control, it’s hard to get tropical houseplants like Calathea to thrive indoors. A lack of humidity is a common cause of brown, wilted, or discolored plants. Yet it’s hard to raise humidity throughout the entire home and risk mildew growth just to help a few houseplants thrive.
Instead, try humidifying just the area where the Calathea and similar plants are located. If you can’t take advantage of a naturally high humidity area like a bathroom, try a reliable method for keeping humidity high.
Humidity trays are commonly recommended, but they’re of limited effectiveness, like misting. These methods will only provide a boost of a few percentage points of humidity directly around the plant.
For a bigger boost when indoor humidity levels are 50% or below in the rest of the house, try a humidifier instead.
Desktop-sized humidifiers are an excellent choice for individual or small groups of moisture-loving plants. Larger humidifiers may be needed for extensive collections of houseplants.
Caring for Calathea Plants in Spring and Summer
Spring and summer are the primary growing seasons for these plants. Long days and warmer temperatures encourage them to maintain good color and growth rates.
Make sure humidity stays high but don’t be afraid if temperatures occasionally dip below 70. As long as the plant isn’t exposed to temperatures below 60 degrees, it should take relatively little extra care to thrive in the spring and summer.
Caring for Calathea Plants in the Winter
Drafts are a significant problem for sensitive Calathea plants in the winter. One blast of cold air from a window or door can lead to dropped leaves. A slow but constant low level of exposure to cool air slowly threatens the plant’s health.
Keeping the plant in a central location in the winter can protect it from temperature fluctuations when doors and windows are opened. Calatheas need less watering in the winter, but they prefer nearly the same humidity and temperature levels as summer.
Avoid temperatures below 60 degrees at all times to prevent leaf loss and sudden wilting from shock. If you decide to use a space heater to ensure the plant stays warm enough, be prepared to use a humidifier to counter the drying effect.
Wrapping Up Calathea Plant Temperature & Humidity Requirements
Calathea plants need plenty of warmth and humidity at the same time. Unfortunately, home heating tends to strip humidity from the air rather than adding to it. Don’t be afraid to use a small humidifier or constant misting to compensate for healthier tropical houseplants like the Calathea. With some practice and a battery-powered temperature and humidity meter, you can easily make these fussy plants happy all year round.
For more, see our in-depth guide to the uses and benefits of calathea plants.