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I stay in the central belt in Scotland are Tree-like Lilies reasonably hardy and do they require special compost and do the bulbs multiply over time?
Tree lilies are very hardy, in fact they like a cold dormant phase and can tolerate down to -25 degrees. They are happy in any well-drained soil and will multiply over the years. After 3 years, remove the bulblets and replant.
Loraine Hart