Can you tell me what is causing my cardinal flowers to die?

Question

The base of my cardinal flowers turn white and then the whole plant bends in half and dies.

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Answer 1

here are several diseases that cardinal flowers are susceptible to, including Botrytis, crown and root rots (Pythium, Phytopthora and Sclerotium), leaf spots (Cercospora, Colletotrichum, Phlyllosticta and Septoria), rust and Sclerotinia. Good cultural practices such as irrigation management, proper plant spacing and plenty of air circulation greatly reduce the occurrence of most of these diseases.
I'm not able to determine which issue effected your plants.