Cardinal flower possible disease
My cardinal flowers turn brown at the base of the plant, and then it moves upward and eventually kills the plant. Can you tell me what causes this and how I can stop it?
Certified GKH Gardening Expert
This could be a watering issues or fungus. If the soil is moist, allow it to dry some between waterings, but make sure that it doesn't become too dry, which can lead to browning. Generally, if it is too wet or receiving too much water, you will see yellowing in the leaves while browning is normally the opposite. This would mean that something could be restricting the roots from taking up any water or nutrients. Check near the roots to see if they or any stems are becoming mushy. Also try treating the plant with neem oil and see if this helps.