Colorado is one of the trickier states to landscape in. It
encompasses no less than five USDA hardiness Zones -- from a
chilly Zone 3 (-40 degrees F) all the way to Zone 7 (0 degrees
F) -- and much of the state receives precious little
precipitation. Combined with higher altitude in some parts of
the state as well as high-pH soils, it can be frustrating for
gardeners of any experience. Fortunately Colorado can be divided
into a trio of regions to provide some landscaping guidance.
About 40 percent of the state -- the eastern edge -- is
considered part of the Great Plains, says Robert Cox, an
extension agent in horticulture with Colorado State University
Extension. The greater region stretches from Colorado and into
Kansas, Iowa, and Oklahoma. The Colorado section happens to be
at a higher elevation than the others, and it has huge yearly
temperature swings -- from -20 degrees F in the winter to days
on end that approach 100 degrees F in the summer. "What's even
weirder is that you'll have days in January wher