It is probably trying to readjust and regrow roots that may have been severed when it was dug up. These are usually grafted onto herbaceous peonies and it's usually recommended to plant the graft quite deep (at least 6") to allow the grafted cultivar itself to begin to grow its own roots.

I have my baby in a pot and it sprouted nicely and has now slowed, but I expected this. In your case, I would let it be since you have dug it and potted it, and hopefully it will recover. Once it does, you should be able to plant it back out again later.

If you bought a tree peony with "lots of buds" it must have been a pretty mature plant and I can understand it being "Pricey". Your mistake was planting it while it was about to bloom. Planting it caused it to go into shock causing the loss of the buds and the wilting. At that point the damage was done and the plant should have been left to recover. Digging and replanting only compounded the shock.As Jenny suggests you should now leave it in the pot at least till the fall to regrow all the feeder roots lost in the transplanting. Al

Thank you for all your suggestions and advice. I do wish the person that sold me the plant had suggested that I wait until Fall. The other ones she sold me transplanted just fine. Just a little wilt, but they popped back within a few days and are now getting ready to open. But they are not tree peonies. I will watch this baby carefully and know that she will be just fine and will recover. Suzy

I guess our first impulse , when we've had a poor outcome from transplanting is to try to reverse the whole process , by repotting the plant , but as said that's even more likely to further damage a plant , that's already in some shock.

What do you do to help a Peony like this in shock, to recover?...A shady location?..or some sun?..how often should it be watered?...Would Super Thrive with the next watering help?...I had a tree peony shipped to me recently...it had one large bud on it and was growing in a pot at the nursery where I bought it online..it had to be completely barerooted for shipment into my state...I have potted it up again and have it in a dappled, semi shaded location...Its leaves look wilted so I know its sufferring from some shock...I removed the bud(figuring it would help if it did not have a flower bud to draw on its energy reserves..maybe it can work on rooting instead...Any help with dealing with shock in Peonies would be welcomed!..thanks GardenLove

Just provide water, but not too much, just enough to keep the soil damp at all times. Don't let potted plants dry out. For plants in the ground, the top few inches of soil can be allowed to dry out, but when you water you have to do it well enough to wet the soil at the roots a foot or more deep, so use a trickling hose for several hours. Provide protection from drying winds and hot sun. Some morning sun would be helpful, peonies aren't at their best in complete shade. Fertiliser will not be needed and could be harmful, so don't bother.

Bare-rooted plants may wilt badly for a few weeks, protect them from all sun and wind. Extra water probably won't help until they have regrown the fine roots to take up the water. After a few weeks, they should be able to get by and you'll just need to keep them watered through the summer.

You might consider sinking the pots into the ground, to prevent drying out. I fill pot edge up even with dirt surface, no lip showing on pot, to prevent pot being a water puddle and not draining well. I dig in all the pots with plants when I can't get them settled into permanent locations for a while, even over the winter. The surrounding dirt keeps the pot as moist as the soil, keeps temps even, not over heated like pots will get sitting on ground in the sun. Cooks the roots.
If the pot will be in the ground a while, I will also move plant to next larger size pot. Just lift out whole pot of dirt, not disturb roots, just add dirt to sides, bottom, top. A touchy plant or very sensitive one will have me cutting smaller pot off to prevent breaking his rootball, or any delicate feeder roots, then transfer into slightly larger pot. This lets plant continue growing over long time, without becoming rootbound. I usually have a great root system for planting time.
Much less work over time with dug in pots, than keeping standing pots watered. Less stress on plants and loss too, as they sit in the ground. No loss of roots when you do move them, just pop the pots out of holes. Plants seem to suffer little shock or stress with removal of plastic pot, replacement in the new dirt hole, they just keep growing in their new home.

Did your tree peony live? I am on my 5th one now and it is not looking good. I bought the first 4 from one of those catalogs that offer lower prices and got bare root plants. They were planted in the fall and lived all through the winter and died in the early summer?? This one I paid a lot more for and it was potted and looked good when I got it, now that it have been planted a few weeks it is just sitting there adn the stem seems to be getting more brown. I called the gardening center where I ordered it and she said it may not be getting enough water?? Everything I have read says to feel down in the soil and if it is moist don't water again, but I am willing to try anything at this point. Please let me know if you were successful---Thanks