Moonbeam Coreopsis Disease?

I know that "Moonbeam" coreopsis was the perennial plant of the year and is relatively disease resistant. In its first year, our Moonbeam was magnificent! In its second, and this, its third year, the plants have not performed well at all. They are not crowded out, nor are they over or under watered. We fertilized with miracle-gro every week. The care was the same both in its glorious first year as well as its disappointing second and third. The plants seem to be "hollow" or getting bare in the center. What's left on the outside circumference of this bare spot is small and does not bloom well. Any ideas? Too much fertilizer? Not enough? Bugs/parasites? (all other plants in the gardens are doing just fine)

Please help....we really love this flower!

The photo does not show how short and "[deleted]" this plant really is. It should be twice as tall and round and filled with a myriad of beautiful little yellow blossoms.

Thanks.

This is the same flower two years ago. What a startling difference.

I wonder if it just needs to be divided in order to be rejunvinated. Some perennials tend to die out in the center like that. I never fertilize mine. Maybe the MG is too much for it to handle. Some plants do better with tough love ;

Another thought is grubs or something in the soil messing with it's roots. I'd dig it up the fall and see if you can see anything weird going on. If it looks okay divide it and replant.

I wonder if the plant is getting enough sun. The first year it would have done fine because it was already underway when you planted it. After that, though, it would respond to garden conditions. Like poppysue, I don't fertilize mine either. In the fall, if I remember, I might toss some compost in the vicinity, but otherwise this plant seems to do well with little care. Regarding division, my plant has been in the ground without division for about eight years. It is a solid clump about 3 feet in diameter. The only thing it seems to need is a haircut after first blooming to keep it flowering.

My Moonbeam coreopsis gets smaller every year. This is it's fourth year and it's down to a few sprigs. I had them planted in three different areas. None had done well after the first year.

It occurs to me after thinking about it that the coreopsis I have that is doing so well isn't Moonbeam--it's an older threadleaf variety, possibly Zagreb, because the yellow color is deeper. I do have two year old Moonbeam plants that are OK, not wonderful, but they are shaded by and competing for moisture with a huge Joe Pye weed clump.

Thank you poppysue, kneff, and Calalily...
I'm not sure if it needs dividing as it was only one year old when it went bad. It is getting lots of sun. I just noticed that another type of coreopsis is doing badly as well.
Maybe Calalily and I are having the same problem? I will dig it up and see if the roots look crummy. Do you think our county agent could shed any light on this?

My Moonbeam looks a bit thin, spread-out and straggly, as does the rosea I got from poppysue. The one that looks best this year is 'Sweet Dreams'... and it was the easiest to cut back for a second flush of bloom mainly because of it's height I have it supported in a cage.

No way has mine ever resembled the nice clump SillyLily posted above!

Maybe coreopsis has health problems?

Sillylily, the county agent might be able to help. They would need a whole piece of the plant, roots and all. They might also know if Moonbeam has problems that we don't know about.

I just read something interesting in a paper from Purdue University. It says that Moonbeam will flower great in it's first year but if you fail to deadhead, it will not flower well in subsequent years. I guess I need to get out the clippers!

S; I'll have to go check on my coreopsis. Havn't been in that area of my gardens since school started. Also not sure if mine is a 'Moonbeam' or not.

I'd be willin to bet that one of the probable causes of why your 'Moonbeam' hasn't faired well this year is because of excessive moisture. I'm sure you know that we were in a draught situation here for the past two years. That condition was just lifted this year after all the rains we got.

It wouldn't hurt to take a sample in to the County Extension office and let them take a look at it.

TC...

Calalily, I'll try to deadhead and see what happens next year.
TC, as for the rain this year, it's been overwhelming here in NW Pennsylvania, but last year was okay and that's when the plants started to decline.
I will take a plant to the county agent office and I'll let you all know what they say.
Thanks for your interest.
SL