Succulents grow either as houseplants or as outdoor plants in warmer climates. Generally, low-maintenance plants that store water in their leaves or stems, succulents grow indoors everywhere and, depending on the plant, can grow outdoors in USDA Plant Hardiness Zones 8 through 12. They generally require little special care, but succulents can develop yellow leaves when growing conditions do not meet the plant's needs.
Succulents store water in their thick leaves and stems. Most of these plants are naturally green, some with variegated leaves and occasionally other colors mixed with green. If you notice some leaves beginning to turn yellow, it is time to step in and quickly fix the problem to prevent extensive damage to the succulent.
Checking the Soil
Overwatering is the most common cause of yellowing leaves on a succulent plant. Constantly wet soil can rot the roots, interfering with the plant's ability to take up water and nutrients from the soil. This interrupts photosynthesis, or energy production, in the plant's leaves and other above-ground parts, and its green color fades to yellow. If left untreated, overly wet conditions can cause leaves to fall or the upper parts of a succulent to soften and rot, eventually killing the plant. Check your plant's soil with your fingertip; if it feels wet, overwatering is likely a cause.
Correcting the Problem
If a succulent has only a few yellow leaves, the problem may correct itself if you stop watering until the soil dries out and then water only when the top 1 to 2 inches (2.5 to 5 cm) of soil feels dry. When a plant starts to drop leaves, it might be necessary to change its soil by removing it from its pot and gently shaking the soil from the roots. Repot the plant in a commercial mix designed for succulents, or make your own. Repot the plant in a container with a large drainage hole and use an unglazed ceramic pot, which allows the soil to dry quickly. When watering the repotted plant, ensure it does not sit in a water-filled saucer.
Checking for Other Problems
If the soil of your plant is a well-draining mix formulated for succulents and overwatering is not the cause, the problem could be the lighting conditions. Most succulents can handle lots of light, but a green succulent takes on a lighter bleached-out yellowish color when grown in too much light, such as full sun for the entire day. Moving the plant into a spot that gets bright, indirect light should correct this problem.
A succulent infested with pests might develop yellow leaves, a sign of general distress. For example, mealybugs, which form a cottony covering on leaves, or spider mites, tiny insects that can cause yellow spots as they feed, could cause the problem. Spraying a plant with ready-to-use insecticidal soap kills these pests.
- Succupedia: Browse succulents by Scientific Name, Common Name, Genus, Family, USDA Hardiness Zone, Origin, or cacti by Genus