Hi Bonfleur, are you zone 5 or 7? I've seen posts from some of the CA peony growers, they successfully grow peonies in large pots, especially Itohs. And I know I saw a pic of one in a pot, think it was in NC, a lady grew them on her apartment patio! So it can be done, don't know if you're doing yourself any favors by sticking them in the ground, though. If you have a drainage problem because of the clay you might just make it worse by putting a pot of good soil down in it. Have you thought of doing a raised bed? Or if you're zone 7 you can probably plant them in a large pot and leave it out all winter, just make sure the peony is good down to at least 2 zones colder because of the pot. I'd think you'd probably want to go at least a 3-5 gallon because of the spreading roots, probably the bigger the better. A nice, large ceramic pot in a pretty color; that would be beautiful with a peony in it!

Hopefully you'll get a response from someone who's actually grown them in pots, I think a lot of the people who posted earlier in the spring have moved on to other things until there is more activity peony-wise. I'd look back at some of the old posts, find a member who has grown them in pots and send them an e-mail. I know I've responded to some questions that have been directed to me that way, most gardeners would be glad to help out!

Thank you for your response. I live in the Treasure Valley near Boise, ID. Our zone ranges from 5 to 7. It's crazy. The raised bed idea is great! You helped me with that one suggestion! If I planted them in containers for my porch or patio, they probably wouldn't survive due to the extreme cold & wind. So, thanks again!

Hello bonfleur,
I know someone who lives in zone 5 and had no choice but to put her peonies in pots. It was recommended to her to put her peonies in half-whiskey barrels as she could expect the rootballs to reach 3 feet across and 2 feet deep in 5 years. If you use other types of pots, make sure they have plenty of drainage holes as the plants need good drainage. Some suggested root pruning so that she could maintain them in smaller pots. (Itohs and herbaceous peonies have larger root systems than trees.)

Overwintering could be done by placing the pots against your house and covering them with a quilt, but if you have an unheated garage, that would be better as there would be fewer temperature fluctuations. That lady in zone 5 overwintered hers in her garage, plus quilt over top, and her plants grew beautifully the next year.

A deep freeze could kill your potted plants, but of course they need the colder temperatures to achieve dormancy. A prolonged period of chilling temperatures is necessary to break dormancy, allowing the plants to flower. A lady (I can't remember on what site) said the temperatures never got cold enough for her peonies to flower.

Black pots absorb a lot of heat from the sun, so you'll have to take that into account if you choose to keep them in pots above ground.

I don't know if you have tree peonies, but you can expect dieback if they are subject to cold hard winds. People have prevented that by putting burlap bags around them over the winter.

I will ask that lady with the potted peonies if she will come on here and tell you of her woes and successes. However, I will be taking the raised bed route, and will be building them up next week. :)

Bonfleur, I saw some posts on a different peony forum with pics of raised beds using the large, slightly curved brick-like things used for retaining walls, very pretty and a single layer would make a nice sized bed, probably only 12-15 blocks so not extremely expensive. Email me if you want the website, I'll see if I can find the exact post. You'll see a few names you recognize from this forum! I like to visit both, the more peony talk the better!