The African Milk Tree (Euphorbia trigona) is a popular succulent known for its unique form and low maintenance. Despite its arid origins, this plant is prone to sunburn from excessive light. Understanding how to identify and address sunburn is important for maintaining the plant’s health and appearance.
Recognizing Sunburn Symptoms
Sunburn on an African Milk Tree manifests as changes in the plant’s stem coloration and texture. Look for yellow, brown, or black patches, often with a dry or crispy feel. These areas are usually found on parts most directly exposed to intense light.
White or brown spots may also develop on uppermost leaves or stems. Mild sun stress might cause reddish or orange hues, but actual sunburn indicates damage. Affected tissues do not typically revert to their original green color, leaving permanent scarring.
Causes of African Milk Tree Sunburn
African Milk Trees experience sunburn due to sudden or prolonged exposure to intense, unfiltered sunlight. They prefer bright, indirect light, but direct midday sun, especially through a window, can be too harsh. Glass can magnify light and heat, increasing scorching risk.
Insufficient acclimation is a common factor when moving the plant to a brighter spot. A sudden shift to intense light can overwhelm plant tissues, leading to damage. Prolonged exposure to direct afternoon sun, particularly in hot climates, can also cause sunburn on the stems. Young or freshly transplanted specimens are particularly sensitive to strong sunlight and heat.
Treating and Recovering from Sunburn
If an African Milk Tree shows signs of sunburn, immediately move it to bright, indirect light. This prevents further damage and allows the plant to stabilize. While the sunburned tissue will not regain its original appearance, minor spots can be left alone.
For severe or aesthetically undesirable damage, carefully prune affected sections. When pruning, wear gloves to protect against the plant’s milky, irritating sap. Proper watering is also important during recovery; allow the soil to dry completely between waterings to avoid overwatering stress.
Preventing Future Sunburn
To prevent sunburn, gradually acclimate your African Milk Tree to brighter light conditions. Slowly increase light exposure over several days or weeks, allowing the plant to adapt. For indoor plants, a south or west-facing window is often suitable, but positioning the plant back or using sheer curtains can help diffuse harsh midday rays.
Outdoors, choose a spot that receives morning sun and afternoon shade, especially in hotter climates. Regularly observe the plant’s response to light changes. Adjust by moving the plant closer to light if it appears leggy, or pulling it back if signs of stress or scorching emerge.