I'm trying to figure out what this is and if I should be digging up the soil, mulch, and plants. This is by the entrance to my driveway. I noticed that my lily plants were blooming fine up until a couple weeks ago they started to brown. I checked the plants recently and there is this powdery white substance at the base of each plant. We've had these plants for many years and they come back each year. What is this and how do I treat this or is this anything to worry about? Is it a disease / blight or mold? Thanks!
