Yellow Leaves on a Kalanchoe Blossfeldiana

Improper Watering or Drainage

• Kalanchoe blossfeldiana can develop yellow leaves as a result of underwatering or overwatering. Allow the soil to dry slightly between waterings. Make sure that the kalanchoe's container has adequate drainage and is never allowed to sit in water. Use a soil mix that provides excellent drainage. Poor drainage will reduce the amount of air available to roots and make them susceptible to root rots. Adjust the watering regimen and amend the soil or container as needed to accommodate the kalanchoe's watering and drainage needs.

Powdery Mildew

• Powdery mildew is a relatively common kalanchoe disease problem and can be difficult to recognize. Sometimes, the only symptom that an infected kalanchoe will develop is a fine webbing. Other possible indicators include mottling or yellow spots, flecks and spotted ring or line patterns. Plants may also be stunted and fail to flower. Prevent the development of this fungal disease by allowing plenty of air circulation around the plant. Control powdery mildew on kalanchoe with applications of a product that contains potassium bicarbonate.

Potential Pests

• A handful of pests may occasionally be problematic on kalanchoe and could be responsible for the yellowing, especially if the infestation is heavy. Typically, other symptoms of pest presence will appear before severe yellowing occurs. Aphids, mealybugs, scales and some types of caterpillars may bother kalanchoes. Inspect the kalanchoe for signs of insect presence. Most pests of kalanchoe houseplants can be controlled easily. For example, control mealybugs by wiping them off of the plant using a cotton swab or cloth dipped in alcohol or simply scrape brown scale insects off the leaves.

Additional Cultural Considerations

• Kalanchoe blossfeldiana prefers full sun or bright light indoors and may become spindly and pale if it does not receive adequate light. Kalanchoe could, on occasion, suffer from a nutritional deficiency. This plant, when actively growing, will benefit from fertilization with a standard houseplant supplement about once per month. If the foliage is becoming pale or the plant has poor growth, it could indicate that the kalanchoe is root-bound and in need of repotting. Gently remove the plant's root mass from the container and examine it. If the roots are brown, rather than white, the roots are probably restricted and the plant should be repotted into a slightly larger container. When plants are relocated indoors or outdoors, make the change gradually to avoid shocking or burning the plant.