Try sprinkling some corn meal around the plants. Its an organic gardening trick used to get rid of weeds and crab grasses in gardens and on lawns.

Having a hot summer? Seems like many of my lilies have gotten "fried" this summer with day after day of high 80s and 90s. The only disease I can think of that it might be is botrytis; this usually kills the leaves from the bottom up until all the foliage is dead. Just in case and to be on the safe side, clean up the garden of all dropped foliage in the fall and perhaps add a thin layer of fresh mulch. This will help prevent any spores from splashing up next spring when the lilies return. Daylilies can also get scorched but I don't know much about their diseases. One bed of daylilies that I have doesn't get watered all summer and even though the foliage seems to scream in pain, they come back beautifully every spring. Yes, a picture might be helpful.

Thanks everyone.

Yes, VERY hot summer and all the ones effected are in a very hot spot. I had some botrtyis on a rose last year but I'm pretty sure that I got rid of it last year? I hope?

I'll take a pic and see if I can figure out how to upload it.

Thanks so much!