If you dig large holes & keep the potting soil as intact as you can when unpotting the daylilies to put into the holes, they will transplant into the ground without even noticing the change.
I repot some daylilies into larger pots each Fall & have had no losses over the Winters here in Zone 7. Always careful to keep the root balls intact, so they don't have to struggle to get new roots established during the cold weather.

Thanks, Hostarina,

That's what I hoped to hear.

I would prefer to plant the new ones in the fall rather than waiting for spring, but lost a couple last year which explains my first ever planting in pots first and allowing the roots to develop. I could put them in the greenhouse, but I can't see a lot of advantage in that.
kay

Sounds good to me too.
Ed

Well, I'm not an expert but I live in zone 8. I've had better results by planting new daylilies in October. If planted in the spring, they don't do much the first year.

Nancy

I also live in zone 8 - our first frost dates are usually mid/late November. I use both methods - I pot when I dont have beds ready for the daylilies. This year, I have raised beds filled with great soil - I buy it mixed, its a combo of mushroom compost, bark fines and sand. The lilies love it, take off and are growing just great. I have learned from experience not to plant them too deep - I have lost them when I planted too deep. I also grow roses and have found that most plants really grow better when planted in the ground. I seem to buy plants faster than I can build beds, so by necessity, I have a good sized pot ghetto. But I steadily work on building beds as I really think they grow better planted in the ground. If you have the readymade beds with good soil - I would suggest planting them there - just be careful not to plant too deeply.

alameda, do you mind telling me the name and where you buy your mixed soil/compost?
I live in the DFW area and should be able to find the same kind.
I have a few daylilies ordered and haven't decided where to plant them yet.

Thank you all for your advice. I will have to let it dry a bit from the heavy rain we got, but I will be planting in a couple of days. That isn't to say that I will be planting all of them immediately, but hopefully all of them very soon.
kay

In zone 5 I've always tried to plant 6 weeks ahead of a hard freeze. The last dls I planted will be 6 weeks on Oct. 23 and so far have went through 2 frosts and probably another one coming over the weekend.