|Last year I had a problem with a black film on the leaves and aphids on my gardenia bushes. I treated them with a pesticide that seemed to clear up the aphids problem. However, the black film has persisted. Any ideas as to what may be causing this problem. All the new leaves arrive free of the film and develop it as they mature.
|Answer from NGA
March 2, 1998
|The black film is likely a sooty mold that grows on the honeydew produced by the aphids. If you are still getting news leaves with mold, your plant probably still has 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.
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