Kalanchoe Disease Management: Phytophthora, Powdery Mildew, and Viral Control

Managing Key Diseases in Kalanchoe Production

Kalanchoe faces three primary disease threats: Phytophthora root and crown rot, powdery mildew, and viral infections. The succulent nature of this crop creates specific disease dynamics requiring targeted management approaches.

Phytophthora Root and Crown Rot

Phytophthora spp. cause dark brown crown/root spots at soil level spreading up stems with wilting, death, and root kill.

Management: Plant in pasteurized potting mix. Discard infected plants. Apply fungicides.

Powdery Mildew

Sphaerotheca humili causes tan scabby leaf spots that may develop white fungal growth or remain scabby.

Management: Apply protective fungicides.

Viral Diseases

Top spotting virus causes mottling, yellow spotting, dead flecks, line/ringspot patterns, stunting, and failure to flower.

Management: Plant virus-indexed cuttings. Maintain insect/mite control. Destroy infected plants. Do not take cuttings from infected plants.

Integrated Kalanchoe Health Program

Successful Kalanchoe production requires: pasteurized, well-draining media (critical for Phytophthora prevention); careful watering to avoid crown wetness; regular scouting for powdery mildew (scabby phase precedes white growth); virus-indexed propagation material; strict insect vector control; and immediate removal of symptomatic plants. The succulent leaves and crown structure make water management at the soil line the most critical cultural practice for preventing Phytophthora.