Western Mountains and High Plains
USDA Hardiness Zone Map
The new, updated USDA Hardiness Zone Map is out and the zones for some areas have changed. For example, my old zone rating of 5b (-10 to -15 degrees F) has been upgraded to Zone 6a (-5 to -10 degrees F).The zones are based on the average lowest annual temperature recorded from 1976 to 2005. That word "average" is important; some years the extreme low temperature will be colder than that, other years warmer. It got to 15 below zero where I live just a few weeks ago and the winter is not over yet. So for the most success, keep track of the actual micro-climate conditions where you garden, which may vary from the more general map data, and do some research on a plant you're considering to determine its native habitat, which can give clues to its cultural requirements and suitability in your area.
Favorite or New Plant
'Green Panda' Bamboo
The selection of cold-hardy bamboos for our region has been limited. I've been growing Green Panda bamboo (Fargesia rufa 'Green Panda'). It grows in a clump-like form and is not invasive. The leaves are an attractive deep green and the green culms (stalks) are covered with reddish-brown sheaths. They do best in well-drained soils amended with a generous amount of compost. Locate in part shade and maintain uniform moisture.