My yield this year was very low. The leaves looked as if they had powder on them, and then the stems started to rot.
Certified GKH Gardening Expert
Yes, it seems you had a bad fungal infection. This could be due to excessive water in the area. Fortunately I have a treatment that is safe, and Extremely effective. There are two parts to this method. Please don't skip the soil priming, as this will bring your pH back to normal, and kill off anything lurking in your soil. If you do not have all of the ingredients to the spray, then that is alright, but the more you have the better. My 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 is an article for more information:https://www.gardeningknowhow.com/plant-problems/disease/get-the-cure-for-powdery-mildew.htm