Why is it hardy from home? Think in geological and evolutionary time frames, not in human time frames. From the sun's perspective, Earth's continents have sailed all over the latitudes and longitudes. The plants dragged along have been through a wild ride. Ceratozamia hildae, with substantial underground stems and storage roots, dwells in lowland Mexican rain forest, but survives temperatures down to the low teens F / -8C with leaf damage. Leo Martin Zone ? Phoenix Arizona USA