Help with Gardenias

Apr 17, 2006 5 Replies

I have 2 large gardenia trees that I winter over in my greenhouse...they have mealy bugs, scale and black mold. Is there any organic product I can use that will not defoliate the plants? If not, what non-organic product would you recommend? Many thanks, Mary


I spray with malathion, but only when I see the pests proliferating. These pests can destroy the contents of a greenhouse because the insects that prey on them generally stay outside.

The black mold (sometimes called "sooty mold") grows on the sugary syrup exuded by the mealy bugs and scale (and by aphids). Get rid of them, and the mold will disappear.

I used a systemic for scale on mine. Probably a good idea to spray them with it again before wintering next year.

My 30+ year old gardenia has a 2 1/2 inch trunk, I sprayed the whole plant when it was outdoors. Scale did not come back. Frank

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