We've had several peony handed down to us roughly 20 years ago. We have never really done anything other than plant, let them grow, enjoy their blooms, then cut down in Fall. While trying to remove Bishops weed that has spread amongst them, (AGAIN! ) I accidentally cut off a piece of root approximately 6 inches long! What should I do, if anything? Is this plant doomed? Please help!

Nothing, I did the same when I moved Festiva Maxima.

Shwew. Good to know.

I don't know how it's going to be affected though. This plant didn't have any bloom this year.

I would plant that root somewhere sunny where you wouldn't mind having a peony. Put the cut side closest to the top of the hole, so the root looks normal. There are some varieties that can grow an new plant from a piece of a root. Mark the spot. It may take a couple of years.

LG - if I didn't save/plant cut roots myself I might have been confused by your instructions to PegNut. The root should of course be planted horizontally

I threw mine away, it's in my compost bin now. Last year I replanted Command Performance with a pip and it was gone this year, the pill bugs devoured it.

Interesting, Val. I plant mine straight up and down (like a carrot) with the cut end just below soil level, and the tapered end at the bottom of the hole.

Don't worry about it; I dug out huge peony that was dormant for decades, did not know it was there till it popped out of a Lily of the Valley garden some years back and got so big it was dominating the garden.

I dug it out last fall and gave it, the chunks to a cousin's wife.
They seem to be thriving at her place so far,
Well as I have found out over the past few decades, peonies can become weeds as despite digging deep and hopefully getting it all out, it is still there and looks quite healthy.
I am going to dig it out and roto-till the whole bed, mom's wild roses, she got them from a road ditch are also spreading like crazy in the same bed.

That said, I have three other peonies I DID PLANT some years back and they looked good till one year three stopped blooming and now no matter what I do, I cannot get two to bloom.
I might did them up and toss them in the Lily of the Valley bed as I KNOW they will bloom there because I do not want them there.

In reality if they do not bloom this year I will dig them up and cut the bottom of the roots off to about one-half foot then replant.

Thank you everyone for your comments. I'll just cross my fingers that it weathers the root cut and bounces back. Now, on to my continued war on the Bishops weed .

Peg, our ducks will eat the Bishops Weed down to nothing by the end of the summer...it does come back st the same strength, but that allows other things to compete with it.

Peg, cutting a single 6" piece of feeder root off the side of a very well established peony isn't going to faze it at all. Those roots are basically food storage and I bet yours has more than enough to weather the loss! I've actually heard of growers removing pieces of feeder root to stimulate root growth....
Now depending on the variety some herbaceous peonies will practically insist on being divided. If you notice your peony putting out less buds than normal years or growing in almost a donut pattern with a bare center you'll want to dig it up and divide it once it goes dormant in the fall. I suppose if yours has been in place for 20 years now with no ill effects you probably won't see those issues! Welcome to the peony forum!