Don’s Expert Answers: Sooty mold killing my native plants in my backyard

Question From:
Loren Knauer in Nerang, Nerang Queensland

Nature of problem:
Sooty mold killing my native plants in my backyard

Type of Plant (if known):
Fiddlewood (on council land)

Symptoms of Plant Illness (please try NOT to diagnose your problems yourself):
sooty mold covering leaves, branches, trunks.

Soil Type (e.g. sandy, clay or loam) OR Potting Mix Type:

How often do you water the plant:
my plants – fortnightly

How many hours of sunlight does the plant get each day:
approx 6

How long since you planted it:
2 years or so

Have you fertilised? If so, with what and when:

Is the plant indoors or outdoors:

Is the plant in a pot or in the ground:

What other treatments have you given the plant:

Upload photo if available:

Other Comments:
Is there anything we can do to remove the sooty mold covering all plants under the canopy of this Fiddlewood. We are in the process of approaching council to hopefully remove the tree and replace it with a local native to the area. Plants I have being affected are Grevillias, bottlebrush, native rosemary. Any advice gratefully accepted. Thank you – Loren Knauer.

Hi Loren, The problem is with the fiddlewood tree. It will have some sort of true bug on it: aphids, mealybugs or scales are the main contenders. These bugs squirt sugary excrement out of their rear ends onto the plants below. The sooty mould grows in this sugary mess. Maybe spray the fiddlewood with Eco Oil. Don