Treatment of fungus
I have two gardenia bushes that have been very productive over the years (250 blossoms on one and 150 on the other last year). This year the lower producing bush blossoms are zero. The cause is apparently fungus (black). Although similarly afflicted, the higher producing plant is OK.
I regularly spray with fungicide (and fertilize). This year, the fungus has been especially prevalent. Should I cut back or what? The fungicide is the garden safe brand--clarified hydrophobic extract of neem oil. What should I do?
Certified GKH Gardening Expert
This is sooty mold. It happens when the plant gets a pest infestation. I would recommend using neem oil, as this will get rid of the sooty mold fungus and kill the pests. Here is some articles that will help you: