In article ,
(Fleemo) wrote:

I have a cherished coreopsis that did spectacularly this summer, but
then started looking sickly. The leaves are silvery gray and the
flowers have stopped coming. I'd hate to lose this plant. Here's a
photo: http://www.inhouzemusic.com/z/coreopsis.html

Any clue as to what is ailing this plant and whether it can be saved?
Come to think of it, I believe this same malady occured to a nearby
scabiosa.

Thanks.

-F

Kinda looks like it is coated with powdery mildew, though I've never seen
it get THAT bad. If that's not a powdery coating then it's not powdery
mildew. But if that IS what it is, it won't necessarily kill the clump if
it was otherwise going to perennialize. But you'll have to clip the
infected plant to the ground, discard rather than compost the infected
leaves, clean up the area super-well, trim back surrounding plants to
permit better air circulation & better sun exposure, & water from the
ground rather than with overhead sprinklers. Spray any autumn regrowth
with dilute milk to keep the powdery mildew at bay, & in spring when the
clump returns in earnest, give it another milky spraying, which works far
better than do chemical fungicides on powdery mildew.

-paghat the ratgirl

--
"Of what are you afraid, my child?" inquired the kindly teacher.
"Oh, sir! The flowers, they are wild," replied the timid creature.
-from Peter Newell's "Wild Flowers"
Visit the Garden of Paghat the Ratgirl: http://www.paghat.com