Lycoris Caldwellii is a cold hardy heirloom is hardy to zone 5.  Most likely it is a natural hybrid.  This sterile triploid has large bulbs and flowers.

Although tollerant of lengthy dry periods, Lycoris do best with regular moisture, even during summer dormancy. As with all Lycoris, I recommend that you plant shallowly, with the top of the bulb close to the surface.  Early planting while temperatures are still warm will give a chance for roots to establish themselves.  When possible we send bulbs with roots.

 Although we take care to send the freshest bulbs possible, it is common for Lycoris to sulk for a year or so after transplanting before gracing us with their summer blooms. This gives all the more reason to get them planted now, rather than put it off for another year.