Coreopsis Rehab

Jackson, MO(Zone 6b)

I have several Coreopsis verticillata 'Zagreb'. They are 3 or 4 years old. The centers have all died out and there are several sprigs outside the "circle". I'm wondering:
1. Why has this happened? and
2. What should I do about it?

Also, I cut the Zagreb back in early July a little to get a second round of blooms. It just died out. Maybe that is what made the plant die in the middle.
3. What do you think?

I know you need to divide this plant, but it seems too soon to have to do this.

My Moonbeam hasn't done this and it's been around a little longer. It also seems to bloom for a longer period. My new shoots of the Zagreb is all over the place. It's not the "mounding" plant I thought I was buying.
4. What has been your experience with either of these two plants?

Pittsburgh, PA

I have grown Zagreb for 6 years and mine seems to ramble . It is not "neat" and mounding in my garden. I try to keep it in an area by moving plants together, but, as it grows new shoots they show up here and there. It is tough.

I have more, mounded neat growth with "star cluster" coreopsis. I have only grown it for two years.

I have tried to grow the pink, varieties and I have had no luck overwintering them.
I bought large plants and they did not survive one winter, here.

None of my coreopsis plants bloom all summer.

Jackson, MO(Zone 6b)

Good to know about the mounding habit of coreopsis. I thought they were sort of "mounding" plants. Perhaps I will plant something else there. Yes, my Zagreb spreads around. It doesn't stay where I planted it, but I thought it was maybe because I had cut it back mid summer. I also was under the impression the Coreopsis bloomed all summer.
Coreopsis v. 'Zagreb' moves around a lot more than Coreopsis v. 'Moonbeam' and doesn't bloom as long either.
The "Star Cluster" is nice. Maybe I will try it or go with something else. I had the Zagreb with Salvia 'Blue Demension' as a border with a Salvia then a Zagreb etc. Some of my Salvia died and the Coreopsis has moved around quite a bit. I think the Salvia should make it. It's really poor soil, but I am improving it a lot with horse manure each time I plant a flower out there now.
Anyway, thank you for replying. It is appreciated.

Pittsburgh, PA

I have bad luck with salvia, I planted many to begin with, they seemed so tough. I had marcus, may night, east friesland, sensation rose, caradonna. The first year they stand up straight, and as years go by they get more gnarly and seem to send their flowers out in any way but upright. The caradonna is the only one that holds it's flowers upright after 5 years. Not thrilled with any of them.

I have great luck with Black and blue sage, it is a real winner, it is hardy in my garden, and is the only plant in my garden that is blooming today. Very long blooming. It is tall, three feet in my garden.

Jackson, MO(Zone 6b)

Interesting comments about Salvia. My Salvia 'May Night' is quite upright. I've had it for many years: maybe 10. It's produced a baby this past year. Salvia 'Blue Dimension' is truly a border plant: stays quite short, about 10", Salvia 'Sensation Rose' is short also. I'm wondering if your soil is a little too rich? Who knows.
Although I'm in zone 6b, Salvia 'Black and Blue Sage' doesn't make it here through the winter. Go figure! Many areas in the United States have a new United States Hardiness Zone, my area did not change, and I think it's pretty accurate.

Pittsburgh, PA

My black and blue sage develops black colored bulbs that are pretty ugly but that is what keeps them coming back. I can send you a few if you are interested? in trying to grow them.

Jackson, MO(Zone 6b)

Well, Yes! I would like to try them. Perhaps they will over winter. It would probably be best to receive them in the Spring. Right? I will pay you for your postage.

Saint Louis, MO(Zone 6a)

Black & blue sage overwintered for me sometimes but definitely borderline. Any moderate winter seems to kill it. I loved it's late season of bloom. I've posted this picture before, but I love the combo of the Black & Blue blooming with fall color in the background. I wonder if snow cover might be a factor - we get little snow, so no blanket of protection from the cold. Just a thought.
I spent the day doing 'getting ready for winter' chores. Gathered up the hoses, tried to carve out some space in the garage to be ready to bring the overwintering plants in, etc. I had been planning to turn our fountain off, but gave in to the pleas of the neighbors to keep it running a while longer.

Thumbnail by Weerobin Thumbnail by Weerobin
Pequannock, NJ(Zone 6b)

Nice neighbors, Wee! Hard to say no to them!
I'm going to have to check the sage for black bulbs. Interesting. I would love for B&B salvia to overwinter.
Birder, in general when a plant dies in the middle, doesn't it need dividing? Is it healthy in the outer ring? I do not grow the coreopsis you mentioned but they are all very common around here and they do spread out in an irregular way. But now that I have an appreciation for the prairie style, I am reconsidering them.
I have many of the same problems you all mention here except I've never selected a coreopsis type that overwintered for me.

(Robin) Blissfield, MI(Zone 6a)

Wee, the birds appreciate your neighbors intervening for them too. Would they appreciate a heater in the fountain for all winter long water? Maybe...just askin' for the birds of course.

I always loved the Salvia 'Black and Blue', thanks for the pics Wee. What zone are you in Obliqua? I have Coreopsis 'Mercury Rising' and it has pretty much grown for the last 3 years with the mounding habit in definite decline this year. This year some of the blooms had even reverted from red to 'Moonbeam' coloring, a soft butter yellow. I do like 'Star Cluster' it's very pretty too.

This message was edited Nov 15, 2016 11:00 AM

Jackson, MO(Zone 6b)

Wee, the fountain looks like a really good one for birds.
Robins should be flying south soon. I did see a flock of them a couple of days ago. And, there was one on my deck this morning.
I've searched for a good bird bath for the birds but they are too deep. It's ironic they call it a "bird" bath.
I have dug up many perennial plants to over winter. Those that are supposed to be "winter hardy", I put on the south side of my house with bales of hay on each side of them. This is a new experiment to see if they will make it. I have dug up MANY perennial plants this year that needed to be divided. I am going to sell them, if they make it, at our Master Gardener Annual Plant Sale.
I dig up my Lantanas each year and pot them up and put them in the downstairs garage.
All of the hoses have been put away.
I have lots of bulbs to plant but think the soil is still a little too warm.
Yes, Loretta, I think you are right regarding the spreading of the perennial and dividing. I've dug up several starts to share with others, and it still moves around a lot.
I'm a little bummed Coreopsis has to be divided so frequently and then, the 'Mercury Rising' is reverting back to light yellow. It's supposed to be an easy care plant. Dividing every two years is not an easy care plant in my books.

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