USDA Plant Hardiness Zone Map
The USDA Plant Hardiness Zone Map
, in an effort to help gardeners know what plants grow well in their region, divides the United States and Canada into 11 areas based on a 10° F difference in the average annual minimum temperature. Keep in mind that local variations such as moisture, soil, winds, adapted species, plant /seed provenance, and other micro-climate conditions affect a plant's viability and can "push" it beyond or below the recommended zone.
The U.S.D.A Hardiness Map is a great reference for novice gardeners or those less patient with trying new plants. All Southern Eucs available on this site had survived in zone 8A even where temps dropped to near record lows of 6°. Most of our initial introductions also grew back from their base in a zone 6B NC winter where temps reached a record 10° below 0.
Eucalyptus mannifera (in trials) flush with burgundy stems during a heavy ice storm.
Abundant and healthy growth at base after multiple days below zero.
One year old Eucalyptus trees feel the weight of freezing rain. All bounced right back as soon as temps warmed.