Silvery leaves on 'Sundown' coneflower

Lula, GA(Zone 7b)

This is only happening on this cultivar, 'Sundown'. The tops of the leaves turn silver-white. It doesn't look like spider mite stippling and the bottoms of the leaves are fine. I cut the plant back a week ago when I saw it was putting out new, green leaves. But now those fresh leaves are turning the same silver-white. Any ideas?

Appleton, WI(Zone 5a)

I never figured it out - mine had that and all the other ones I saw did that.

Lula, GA(Zone 7b)

Was it just your 'sundown' too? Hmmmm

Appleton, WI(Zone 5a)

I got rid of mine, I thought it resembled botrytis, but that wasn't it.

McLean, VA(Zone 6b)

I have this problem with summer sky. I think that it is powdery mildew since I could wipe it off the stems. I haven't seen it on magnus or white swan, but I did have it badly last year on after midnight as well.

Lakes of the Four Se, IN(Zone 5a)

I have the same problem with Sundown. I moved it last fall so now it has good air circulation. Guess what? Still got mildew! This one probably needs a good dose of neem oil or something similar, applied regularly throughout the growing season.

Lula, GA(Zone 7b)

Interesting. I have 2 also and they both have the problem, but it's not mildew - doesn't wipe off (and I've sure had PM on bee balms and phlox). It's a hard, almost crusty white. But only Sundown.

McLean, VA(Zone 6b)

Is this what your leaves look like?

Thumbnail by pennefeather
Lula, GA(Zone 7b)

hi pennefeather. hard to say, the light is so bright in the picture, but I think it does look that way. All over white, not patchy, crusty feeling, doesn't rub off. Thanks

Lakes of the Four Se, IN(Zone 5a)

That's exactly how mine is, too. I always thought it was mildew, but it's very crusty and doesn't rub off. Disappointing, but at least we can take comfort in knowing that it's the cultivar and not our gardening practices.

Lula, GA(Zone 7b)

you are so right Figaro. It's good to be validated!

Upstate, NY(Zone 5a)

Mine has it too!! Did the same thing last year but didn't affect the other coneflowers in the same area so I thought it might just be that cultivar (not sure that is the right word) that does that??

Chattanooga, TN(Zone 7b)

could it be sunburn?

i am growing some in the sun that look just like the picture and others in a semi-shady location that have usual/normal colored leaves.

Upstate, NY(Zone 5a)

Doesn't seem to effect the plant......so maybe it is??

Athens, PA

My Sundown did it too. None of the other varieties looked like that, so I figured it was the cultivar. I chucked mine too.

Lula, GA(Zone 7b)

This has been very interesting. It seems we should "report" this problem to someone! I hate for more gardeners to waste $5-10 on a plant with a defect.

Appleton, WI(Zone 5a)

It is good to hear some similar result to what I noticed, the leaves doing that wouldn't have been a concern if the plant didn't sort of wane after that.

Chattanooga, TN(Zone 7b)

you just made me go out in 105 degree heat index and look!

seems the ones i have in semi-shade (afternoon sun past 3 pm) have normal colored leaves. flowers need to be dead-headed
the ones in full sun have the silvery leaves - need to be dead headed also - but plants don't seem to mind, they are putting out new growth.

Lakes of the Four Se, IN(Zone 5a)

I'm ready to chuck mine. This is the 3rd consecutive year with this problem. For me it's not an air circulation problem, and it's not leaf scorch. I usually prune it back and then it grows half-way decent foliage and tries to bloom a little in the fall. It's just so UGLY and it's taking up valuable space.

(Clint) Medina, TN(Zone 7b)

This plant is a disaster...I ripped all of them up and they now are in a ditch rotting some place. LOL.

Lula, GA(Zone 7b)

Thanks echi- now I know what to do with the one I left in my nursery bed. There is no hope if you could not make it work.

This message was edited May 5, 2009 7:16 AM

Lakes of the Four Se, IN(Zone 5a)

Only the purple ones do well for me. Sunrise has failed me twice, and White Swan decided she wanted to be purple again! I still have Sunset and plan to neem oil the daylights out of it this year and see if that prevents the mildew problem. If not, out she goes!

Mona in Metcalfe, ON(Zone 5a)

echies dont need a lot of water and if you do water them only in the early morning at ground level they are very hardy and should only be watered if it hasnt rained in a week or so and not to much or mildew forms

Lakes of the Four Se, IN(Zone 5a)

I usually don't water mine since they are so drought tolerant. It's very humid here in the summer, and that seems to be a culprit.

Mona in Metcalfe, ON(Zone 5a)

the leaves looking silver could just be that it got really hot real quick and the leaves just got sunburned that is what it looks like so I would not worry about it and just enjoy the blooms

I have about 50 plants that I started from seed last year and should all bloom before the end of the summer I am so impatient to see the different colors

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