Certified GKH Gardening Expert
I have a method that is powerful, natural, yet gentle enough to be used at any time, and as often as needed. The method is as follows:
First, you will want to prime the soil with dolomitic lime, then spread wettable sulfur to Kill off any infection in the soil. I Also like to spray the plant itself. Mix a few drops of one or more of these ingredients into warm water with a spoonful of coconut oil: Rosemary oil, lavender oil, neem oil, garlic oil, cinnamon extract/oil and for really bad cases, also add clove oil.
Here are some other organic means of controlling pests: https://www.gardeningknowhow.com/special/organic/natural-home-pesticides-organic-garden-pest-control.htm