Don’s Expert Answers: Unknown growth underside of leaves

Question From:
Kevin in Mosman, Sydney New South Wales

Nature of problem:
Unknown growth underside of leaves

Type of Plant (if known):
Little gem magnolia

Symptoms of Plant Illness (please try NOT to diagnose your problems yourself):
White cotton looking growth underneath leaves. Ants feed on the growth.

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

How often do you water the plant:
Never

How many hours of sunlight does the plant get each day:
1

How long since you planted it:
Unknown

Have you fertilised? If so, with what and when:
Unsure, just moved in. Bought osmocote for roses.

Is the plant indoors or outdoors:
Outdoors

Is the plant in a pot or in the ground:
Ground

What other treatments have you given the plant:
None.

Upload photo if available:

Other Comments:
Help! Just moved in to new place and leaves have strange white substance growing underneath. I can’t seem to find any corresponding images online.

Answer:
Hi Kevin, Your poor ‘Little Gem’ is very ill due to lack of sunlight. The white stuff is an exudation from mealy bugs which are insects. The plant has lost its defence against pests and diseases due to lack of sunlight. Dig it up between now and the end of August and re-plant it on full sun all day long. You can spray the mealy bugs with Eco Oil, make sure that you spray directly onto the white stuff. Chances of recovery 50%. Good luck. Don