I don't know why it is the only plant to get it but it doesn't make sense. The plant is in my makeshift greenhouse so the leaves are dry. I do not get them wet when I water it but it has powdery mildew. I hope that I am right that it is powdery mildew, well wrong if it is nothing but I see way too much of this every year. I have a copper fungucide I can use. The upper leaves have nothing on them and the plant is growing very fast even though it is still cold here. I did see a couple aphids in it and have been collecting lady birds to eat them so they don't get bad. Is it normal for lower leaves to get it in a greenhouse type setting even though the lower leaves stay dry when I water the plant, or as dry as I can keep them anyway?