My Dracaena Marginata Is Dying

Cultural Precautions

• To prevent fungal and bacterial infections that can kill your Dracaena, let the soil dry between watering. Your Dracaena will do best if the indoor temperature is from 60 to 79 degrees F during the day and 10 degrees cooler at night. Main soil pH between 6 and 6.5; anything above that can cause the leaf tips to turn yellow.

Fusarium Fungal Rot

• Fusarium leaf spot and stem rot caused by the fungus Fusarium moniliforme causes irregularly shaped reddish-brown or tan lesions on new leaves in the central whorl of Dracaena leaves. These lesions sometimes have a yellow border. If you keep your plant wet and do not let it dry out, the disease will spread to other growing parts. Horticulturalists at the University of Florida recommend a fungicides containing the active ingredients thiophanate-methyl.

Erwinia Bacterial Infection

• If the stem ends of your Dracaena are brown, mushy and perhaps smell like rotting fish, they likely infected by soft rot caused by the bacteria Erwinia carotovora pv. Carotovora and E. chrysanthemi. These bacteria cause a slime that can discolor Dracaena leaves and cause them to collapse. They grow on plants that are overwatered or allowed to sit in water. There are no accepted chemical controls for these bacteria. Try cutting away the diseased parts. If that doesn’t work, destroy your plant to keep the infection from spreading.

Mealybugs

• If there are white cottony masses on the thick part of the leaves of your Dracaena, it may be infected by mealybugs. You may see honeydew, a secretion from the mealybugs, and a fungal sooty mold that forms on the honeydew. Mealybugs can stunt the growth of your Dracaena and kill it. Horticulturalists at Colorado State University recommends insecticides containing the active ingredients bifenthrin, permethrin or tetramethrin on mealybugs.

Scales

• If you spot light to dark brown spots hardly larger than a pinpoint on your Dracaena, your plant may be infected with scales. These round to oval-shaped insects are difficult to spot, but they can weaken, stunt or kill a Dracaena by feeding on the stems and leaves. Spray your Dracaena with a diluted horticultural oil to smother the scales.