What Is Wrong With My Jacaranda Tree?

Is there a white layer formed on the branches and nearby surfaces?

Are the leaves yellow with dark margins?

Are the leaves yellowing, wilting and, dying?

Are the leaves curled and distorted?

Are the leaves of your camellias yellow and are the leaves and stems covered with small bumps?

Glassy-winged sharpshooters drain jacaranda leaf fluids. The fluid waste they excrete dries to form a white layer on the branches and nearby surfaces. These bugs transmit the deadly Xylella fastidiosa bacteria. Organic insecticidal soap controls these pests, but complete control on large jacarandas requires patience.

Yellow leaves with dark margins are the first symptoms of Oleander scorch, a bacterial disease caused by Xylella fastidiosa. This is the most serious of the jacaranda tree problems you are likely to encounter. The bacteria move inward from the tips of the leaves to their bases, and eventually through all the branches. As they plug the water-transporting xylem tubes, the tree slowly dies of thirst. There is no cure for oleander scorch.

Yellow leaves that wilt and die usually indicate Root rot. Several pathogens can be the cause of root rots. Poorly drained, overly wet soil promotes rot so choose well-drained sites and add organic matter to improve drainage. Remove and destroy infected plants.

Distorted and curled leaves are caused by aphids. These tiny insects cluster under leaves and on growing tips where they feed on plant sap. Leaves, stems, and buds get distorted and later leaves and flowers drop from the plant. You can control them by washing them off the plant with water spray. Insecticidal soap should be used with severe infestations.

Yellow leaves covered by small bumps are caused by scales. These tiny, shelled insects often feed on the undersides of the leaves, causing an unhealthy appearance with yellowish blotches on the upper leaf surfaces. Scrape off minor infestations with your fingernail. Prune out badly infested growth, or use a soft brush and soapy water to gently scrub the scales off the stems. Control scales by spraying insecticidal oil during the growing season.

Excessive fertilizing may lead to damaging soil levels of minerals or salts, causing dead leaf tips and yellowing leaf edges. If a tree has these symptoms, the best way to pinpoint the mineral responsible is with laboratory soil and tissue tests.