These are pretty hardy. What are they like now several days later? Did you replant it deeper? I'm sloppy about moving them and find 'em hard to kill.

If they were in pots, the best plan is to plant them as deeply as they were in the pots.

Another clue would be to cover the parts of the stems that are lighter in color.

I have planted these several times with varying results, but I always assumed it was because of differences in soil, moisture, and exposure...maybe the depth planted is also significant. I have found them quite awkward to plant.

If they don't soon stand up on their own, though, they probably need to be deeper. You could try supporting them with a bit of mulch or leaves instead.

Possibly the roots "smother" if they are much deeper than an inch.

The type of soil you have may make a difference, too. My soil is very heavy, with a lot of clay, and one inch is about right to hold the plant upright. If your soil is lighter, more depth may be safe for you.

They do like moisture, so if your soil is not very moisture-retentive you may want to add some heavier amendments.

Thanks for the replies. I did end up burying them a little deeper (the lighter parts) and they are doing much, much better. I think I lost one so I have four surviving plants, but I hear they naturalize so hopefully they'll multiply. They are standing straight up now and hopefully they'll bloom soon.

I, too, have heavy clay soil, but I did amend it with some top soil. Either way, it is extremely moist and we have had quite a bit of rain lately. Today, Easter, is very chilly, but I think temperatures are supposed to climb steadily from now on. We'll see.

Again, thanks for the replies and I'll post some pictures if they come to life.