Answer: Bulb lilies (Lilium) should be left in the ground for winter. They are hardy and should be fine assuming they are planted in a spot with good drainage (meaning it is not soggy during the winter). You can gently remove the spent tops and, once the weather has turned cold, mulch over the bulbs with several inches of organic mulch such as shredded bark. You might also want to mark the spot where they are planted so you know where they are next spring.
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