Bacterial Leaf Spot and Stem Rot | Infected leaves and stems become wet and slimy. Cuttings rot. Roots of established plants turn black and die. | Erwinia chrysanthemi, E. carotovora pv. carotovora | Purchase plants free of the disease. Discard infected plants. |
Fluoride Toxicity | Leaf tips and margins brown and die. | Excessive fluoride | Maintain a soil pH between 6.0 and 6.5. Do not use water containing more than 0.25 ppm fluoride. Do not use a potting mix with perlite or superphosphate fertilizer. |
Fusarium Leaf Spot | Tan to red-brown, oval spots form on the tips of young leaves. Spots have a bright yellow halo. | Fusarium moniliforme | Avoid overhead watering. Apply a fungicide to protect healthy plants. |
Fusarium Stem and Root Rot | Lower leaves yellow and wilt. Roots are brown. Tan spots form on the stem at the soil line and may b covered with powdery, yellowish spores. | Fusarium | Avoid overhead watering.Apply a fungicide to protect healthy plants. Discard infected plants. |
Phyllosticta Leaf Spot | Small, round to irregular spots form on older leaves. Spots have purple borders and yellow halos. | Phyllosticta dracaenae | Avoid overhead watering. Apply a fungicide to protect healthy plants. |
Phytophthora Leaf Spot | Leaves near the soil are water-soaked and have brown, irregular, zonate dead areas. | Phytophthora nicotianae | Plant in pasteurized mix. Discard infected plants. Apply a fungicide to protect healthy plants. |
Poor Color | Plants appear dull, mostly dark purple to maroon and lack rose or pink tints. | Plants appear dull, mostly dark purple to maroon and lack rose or pink tints. | Maintain moderate fertilizer level. Shade in the summer but add light in the winter if too low. Maintain moderate temperatures. |
Tip Death | Very young leaves die but the plant recovers. | Damage from fertilizer or leaf shining chemicals. | Keep fertilizer off the growing point and young leaves. Use leaf shining chemicals carefully. |