QuestionsHow to growFlowersBorder Perennial Flowersarum lilies 0 Vote Up Vote Down Catherine Kavanagh asked 14 years ago I have a large clump of Arum Lillies, I would like to move them. When should I lift them, and could I grow them from the seed heads. 1 Answers 0 Vote Up Vote Down Gerry Daly Staff answered 6 years ago Arum lilies can be moved easily in autumn or winter when the foliage has died back. Â The seeds are easy to germinate, sown as soon as they are fully ripe, even in the soil outdoors or in pots in a greenhouse or window sill indoors.