Crinum Hardiness Temperatures

Crinum in Tropics

• In U.S. Department of Agriculture zones 9 and 10, the crinum is an evergreen. With low temperatures reaching only 20 degrees Fahrenheit during the coldest winters in Zone 9, the bulb flowers and retains foliage year-round. It may be used as a hedge, a low screen or in scattered plantings throughout the garden.

In Lower Zones

• In U.S. Department of Agriculture zone 8 and even in zone 7, foliage will die back when frost or freeze occurs. As a herbaceous perennial, foliage may return in the spring if properly mulched. Foliage dies back at temperatures of 25 degrees Fahrenheit or lower, while the actual bulb may survive. Similar to other bulbs, such as the tulip, crinum requires a period of cold, 35 to 45 degrees, for optimum performance.

In Northern Zones

• Once planted, the crinum prefers to stay in one spot. Crinums may be lifted and stored for the winter, preserving as much of the root system as possible. In more northern zones, crinum bulbs may be grown in large containers and overwintered indoors at appropriate temperatures.