The String of Bananas plant is a popular succulent known for its unique, trailing banana-shaped leaves. Many observe their foliage developing a distinct purple hue, a common change that often prompts questions about the plant’s health. Understanding the reasons behind this transformation is key to providing optimal conditions.
Understanding Purple Coloration
The purple coloration in String of Bananas plants is primarily due to pigments called anthocyanins. These natural compounds are responsible for red, blue, and purple colors in many plants. Anthocyanins serve as a protective mechanism, shielding them from excessive light and environmental stresses. For succulents, a slight purple blush indicates a healthy stress response, often signifying the plant is receiving ample light and thriving, leading to vibrant coloration. Conversely, an intense or unhealthy purple, sometimes with other symptoms, might signal distress or an underlying problem.
Common Causes of Purple Hues
One frequent reason for purple hues is exposure to high light levels. Direct sunlight or very bright indirect light stimulates anthocyanin production, resulting in a healthy and vibrant purple coloration. This is a desirable outcome for many succulent owners, as it intensifies the plant’s natural beauty. String of Bananas plants thrive with bright light, which can lead to this characteristic purple flush.
Underwatering or drought stress can also contribute to purple discoloration. When the plant experiences prolonged dryness, it undergoes a form of stress that can trigger protective mechanisms, including the development of purple pigments. While these succulents are drought-tolerant and store water in their fleshy leaves, extended periods without water can cause the leaves to shrivel and potentially turn purple as a survival response.
Temperature stress, particularly cooler temperatures, can induce purple coloration. While String of Bananas plants prefer temperatures between 60°F to 80°F (15°C to 27°C), a slight drop in temperature can encourage anthocyanin production as a protective measure. Extreme heat can also cause stress, sometimes manifesting as purple or other discoloration.
Nutrient deficiencies, though less common as a primary cause for purple in succulents, can sometimes play a role. A lack of certain nutrients, such as phosphorus, can manifest as a purplish tint on foliage. However, this is usually accompanied by other symptoms like stunted growth or overall poor vigor, making it less likely to be the sole reason for a healthy plant turning purple.
Addressing Purple Color Changes
If the purple coloration on your String of Bananas plant is a desired aesthetic, maintaining optimal light conditions is important. Providing bright, indirect light or several hours of direct morning sun can encourage vibrant purple hues without harming the plant. Rotating the plant regularly ensures even light exposure to all sides, promoting uniform coloration.
When purple indicates a problem, specific adjustments to care are necessary. If underwatering is suspected, thoroughly water the plant until water drains from the bottom, then allow the soil to dry completely before the next watering. String of Bananas prefers soil that dries out between waterings, typically every one to three weeks depending on environmental factors.
For purple accompanied by signs of too much light, such as scorched leaves, move the plant to a location with slightly less intense light or provide filtered sunlight. Harsh midday sun can be too strong. Protecting the plant from temperature extremes, particularly cold drafts or temperatures below 50°F (10°C), is also beneficial for its overall health. If nutrient deficiency is suspected, a balanced, diluted succulent fertilizer can be applied sparingly during the growing season.