In general,

The best time to plant lilies is in the Fall, the second best is in the spring, anytime in winter is OK if you can hack the ground up, but the summer is getting dicey. It gets more dicely the colder the zone since they've lost their spring growing and confront an early winter.

Now, if they're cheap enough it's worth the gamble.

What you definitely DON'T want to do is buy them and hold them. Lily bulbs never go truly dormant - and these have probably been out of refrigeration for awhile anyways.

If you buy them now put them in the ground immediately so they get as much growing season as possible to produce leaves and photosynthesize for awhile to build up the bulb before they go dormant for the winter. To make things even better remove any flower buds that form so all the plant energy can go into the bulb. Late planted bulbs have artificially late bloom and late blooming lilies don't do as well in cold zones. They'll "reset" next year and bloom on time.

-Helen

Thanks...we'll give it a try and see what happens... :)