I have a transplanted young Columbine, which is unhappy. I water it regular and it sits in a west facing window. It is constantly getting powdery mildew, and its leaves die back on a regular basis. It also hasn't grown above 5cm tall, but yet I've had it for a year! I don't know what to do, please advise.
Columbine as a Houseplant
Certified GKH Gardening Expert
It sounds like the moisture or humidity conditions indoors must be just high enough to create an ideal situation for the powdery mildew to grow. Neem oil can help with this. Here is more information: https://www.gardeningknowhow.com/problems/pests/neem-oil-uses.htm