I've never had any problem overwintering even the more tender floral mums in the ground. My parents even overwintered them in relatively small pots on their patio last year. A few decades ago, when winter temperatures were much more extreme, I'm sure overwintering them was more difficult here.

My crystal ball tells me that your soil may have poor drainage, but the images in the crystal are very dim. More information from you might clear up the picture.

Maybe not enough water , I don't know maybe I did not give them enough time in the spring to come back. now that I think about it they would be late coming back up. I will try again......Thank you so much, now that I Know that it can be done. I will try harder..

For me the mums are hit or miss. Some come back for a year or two, some not at all. The most reliable came from a pot I bought at Walmart ten years ago for $2.99. Here are some tips that I've heard from gardening friends. Mums don't like wet roots. Notice they have hollow and brittle stems, so don't cut them down in the Fall or they will drown. Let them die back naturally and cut off the dead stuff the following Spring. You'll see new growth pretty early. Once they get 3-6 inches tall, cut them back. This encourages full plants. Cut off the buds by the Fourth of July if you want them to bloom in the Fall. Otherwise they'll bloom in August. good luck!

All of mine are over 10 years old. I remember one seemed a little finicky for the first couple of years (just barely making it through winter), but now does as well as the others. All of mine are the tender "florist-type" mums. The hardier "garden-type" mums should be much much less fussy. I think Bluestone has a good selection of the hardier types.

I don't know if cutting mums back sometimes causes issues, but I always remove all the top growth from mine in late fall/early winter. The hollow-stem/rot problem is a definite problem with some perennials, but it doesn't seem to be for any of my mums. I leave only about a half of an inch of stem sticking up above the mulch, and haven't had a rot problem at all.

BTW, if want your mums smaller (less floppy) and fuller (less lanky), keep them trimmed back until July 4th and then let them go. If you wait until then and do all your pruning at once, I'd think you'd loose some potential blooms/bloom-time-length and have less satisfactory results. I usually try to prune mine at least three times before fireworks day.