Had a botrytis blight strike my plants in self-watering planters on my covered patio. I have majorly cut back on many of them, sprinkled with cinnamon and sprayed with Neem oil. My peony has majorly suffered from this and has brown creeping up its stems (normally green) from their base, but the leaves are healthy. Although I have had to remove stems with leaves that were fine one day and were totally limp the next. Is it the fungus eating through the stem? It only has two surviving stems left! How do I stop this?!?