I live in Chicago and have Stargazer lilies in large plastic containers. How should I winterize them?
Dig up the bulbs and store them in ventilated bags (onion sacks) in a cool room out of the sun. Make sure to wrap the bulbs in moist (damp, not wet) newspaper, or put the bulbs in bags of barely moist peatmoss sphagnum. The material must be damp, not wet. If the bulbs are allowed to dry out, they will die. If kept too wet, the bulbs will rot. Check the material (sphagnum/newspaper) every few weeks to re-wet it if necersssary. The cooler you keep the bulbs the better (above freezing).