What can I spray on the leaves or add to the soil to get rid of the black mold on my gardenia bushes? What causes this? |
The black film is likely a sooty mold that grows on the honeydew produced by the aphids. You can spray with insecticidal soap to get rid of the aphids, and this may wash off the sticky coating and the mold as well. If not, you may need to wipe each leaf with soapy water. |