Black stems on shasta daisies
Plants grew and blossomed well then stems starting turning black .I pulled some out and the root system was kind of lacking. Slug damage? Grub damage? I don't think grubs,haven't seen any. I have another plant in my back yard and same thing.We did have a lot of rain earlier in the summer which effected my potted flowers a bit...And it seemed to have affected the center of the plants primarily.
Submitted by BHGPhotoContest

It's possible that the wet weather provided an ideal habitat for a bacterial disease to attack your shasta daisies (Leucanthemum x superbum). They require well-drained soil, and if the soil was constantly soggy, their roots may have rotted in the ground. If that's what happened, all you can do is amend the soil with a lot of organic matter (compost, shredded leaves, etc.) to improve drainage before you replant. The black stems and skimpy root system you describe doesn't sound like the kind of damage slugs leave behind, and if it were grubs, you'd not only see them in the ground, but you'd also notice other dying plants in your garden and turf in your yard.

Answered by BHGgardenEditors