In my zone the rain and winter freezes would cause them to rot. Amaryllis (Hippeastrum) hardy zones from 9-11 sometimes 8 in sheltered areas not to much water in winters where freezes will cause rot. I have left some on patio in pots in my zone 6 pots covered and sheltered in dry soil they did well for a couple of years until a really odd ball winter, really cold icy winter came along and they had froze causing bulb rot.
I do have Naked Lady Amaryllis Belladona cold hardy from zones 7-11. I'm in zone 6 . They are in a sheltered area with fast draining light soil. They have naturalized in the garden and flowered on cue for the past 20 years. Happily they are deer and gopher proof.
Holidays it's fun to force amaryllis bulbs inside. Some of the bulbs were disappointing this year. I will stay with better bulb sites next year did not like any of the waxed bulbs very odd, short and stubby and didn't open all the way and the other bulbs were purchased on sale were all disappointing.
