Hi, I planted several species of Dietes years ago in my yard in
central NM (USDA Zone 8a or 7b) and while some lasted for several years, winter
eventually got them all. I think it was more the duration of freezing
weather than the actual low temperatures that got them here. They
just quit trying after a while - no reserves left. They were all up next
to the south wall of the house.
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