I see bare root for sale all the time in bags at Walmart every Spring. I never bought any, but it feels like the dark bags have peat or something in them to help them stay slightly moist. The bags are dark (black), so maybe it tricks the daylily roots into thinking it is winter dormancy. I don't know for sure. But if that is the case, you could use black trash bags with some small holes punched into it, add slightly damp peat and place all your daylilies in it. Be sure to remove most of the green foliage to prevent rot.