Answer: You didn't say what kind of lily you are growing or whether it is inside or out. So, I can't give specifics but just general information. Foliage may brown if you under-water or over-water, if there is a fungal disease present, or if the plant leaves are burned in hot afternoon sunshine. To avoid over-watering, make sure the soil drains quickly and that the top inch dries out before watering. Best wishes with your lillies.
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