I got sick of digging and planting, digging and storing, a few years back. So, I potted them all, and now I just cut off the tops after frost, let them pots dry out a few weeks in a dry place (garage or greenhouse), then store in my basement or barely-heated attached garage.

They store MUCH better this way than when dug. I used to have problems in particular with glads and dahlias rotting. Not now.

Of course, it does take a bit of room. I've got about 30 pots of various bulbs, most are in 18" square containers, and a few are larger tubs about 22". I just tuck the pots under of behind things, and I also stack them 2 to 3 deep if possible.

They go back outside in mid to late April after the danger of hard freezes is over.

I think it is of benefit to grow a lot of tender bulbs in containers, as many of them require a good deal of soil heat to get started in spring as well as hot conditions to bloom well and containers heat up faster than inground conditions and you can move or place the pots to receive maximum sun and heat to encourage flowering.

They've come back for me the last 2 years (and last year was a pretty harsh winter temps wise for me....coldest so far in SCS in 7 years)

~Chills