Kalanchoe plants are popular succulents, known for their vibrant blooms and simple care. While these resilient plants are often considered low-maintenance, understanding their specific temperature preferences is important for their sustained health and prolific flowering. This article explores Kalanchoe’s temperature needs, guiding growers to provide an optimal environment.
Ideal Temperature Range for Kalanchoe
Kalanchoe plants thrive within a temperature range that supports both healthy growth and abundant flowering. Their preferred conditions fall between 60°F and 85°F (15°C to 29°C). This range mimics the moderate climates of their natural habitats, allowing them to flourish without experiencing undue stress. During nighttime hours, Kalanchoe can tolerate slightly cooler temperatures, ideally not dipping below 50°F (10°C). Maintaining these conditions helps ensure the plant’s metabolic processes function efficiently, promoting robust foliage and consistent blooms.
Kalanchoe Cold Tolerance and Protection
Kalanchoe are sensitive to cold temperatures, especially frost and freezing conditions. When exposed to freezing temperatures, the water within the plant’s leaves can freeze and cause cells to burst, leading to mushy or blackened foliage. Temperatures falling below 50°F (10°C) can cause stunted growth and a reduction in blooms, while drops below 32°F (0°C) may be fatal.
To protect Kalanchoe from cold, bring indoor plants inside when outdoor temperatures consistently drop below 55°F (13°C). Positioning them away from cold drafts from windows or doors is also beneficial. For Kalanchoe grown outdoors in regions prone to cold snaps, temporary measures such as wrapping plants in plastic film or fabric, or even setting up a temporary greenhouse, can provide insulation. During cooler winter months, reducing watering is important, as the plant’s growth slows, making it more susceptible to root rot if the soil remains excessively moist.
Kalanchoe Heat Tolerance and Protection
While Kalanchoe are succulents adapted to warm environments, extreme heat can still be detrimental, especially when coupled with intense, direct sunlight. Temperatures consistently above 85°F (29°C) can lead to stress, impacting their ability to flower and grow effectively. If temperatures exceed 106°F (41°C), the plant’s growth may cease entirely, and it becomes more vulnerable to wilting and sunburn. High nighttime temperatures, specifically above 70°F (21°C), can also delay flower initiation and reduce the overall quality and quantity of blooms.
To safeguard Kalanchoe from heat stress, providing shade during the hottest parts of the day, particularly during peak afternoon sun, is important. This is especially relevant for outdoor plants or those near south- or west-facing windows indoors. Ensuring good air circulation around the plant, possibly with the use of a fan in enclosed spaces, can help dissipate heat. Avoiding placement near artificial heat sources like radiators or heating vents also prevents localized overheating.
Signs of Temperature Stress in Kalanchoe
Recognizing signs of temperature stress allows for timely intervention. When a Kalanchoe is exposed to excessively cold conditions, its leaves may become mushy, discolored, or exhibit water-soaked necrosis. Prolonged cold can also result in general wilting, withering, or a lack of flowering and stunted growth. In severe cases of freezing, leaves may turn black, indicating significant cellular damage.
Conversely, signs of heat stress often include leaves that wilt, even if the soil is adequately moist, as the plant attempts to conserve moisture. Brown leaf tips, general yellowing of the foliage, or stunted growth can also signal overheating. Sunburn, a common consequence of excessive heat combined with intense sunlight, manifests as yellow, white, or pale areas on the leaves, sometimes with brown or black spots, particularly along the edges or tips. Affected leaves may also feel dry and brittle to the touch, losing their typical plump, succulent texture.