As I go about my work in early spring, I frequently look to the west, where I can see the foothills of the Rocky Mountains. Less than a mile from our nursery, they rise to 8,000 feet and are usually green at this time of year. I can easily make out the ponderosa pines, the rock outcrops, and the open, grassy areas that prevail there. This is a beckoning sight, especially in the spring, when many of the native plants I love are reawakening and starting to bloom.
The foothills around Fort Collins support many beautiful, unique perennials and bulbs that burst into flower as soon as the weather permits. The botanist in me is enthralled by the floral diversity our foothills offer—the clear white, straplike petals of sand lilies (Leucocrinum montanum; above); the furry, soft blues of pasqueflowers (Pulsatilla patens); the oversize, simple pinks of ball cacti (Pediocactus simpsonii); the bold, dark blue, leathery bells of the sugarbowls clematis (Clematis hirsutissima). All of these plants grow in the drier, more exposed foothill areas. I've had great success in cultivating many of these natives. They are easily grown from seed collected in mid-to late summer, dried for a month or so, and sowed in late fall for a winter chilling period before germinating the following spring.
Where constant moisture and a northern exposure exist, some rare foothill gems are to be found, such as the red-flowered wood lily (Lilium philadelphicum) and the lady's slipper orchid (Cypripedium calceolus subsp. parviflorum), with its large yellow pouches and curling tendrils. Both of these plants migrated from the upper Midwest when the climate was much wetter, and were left behind as the region became more arid (forever a reminder that plants can move if given a few thousand years to do so).
Once you get really acquainted with a plant and its native distribution, you can start to see the differences that botanists call forms or subspecies. I've selected two forms of sugarbowls clematis—my favorite, and a plant with perhaps the most garden potential of any native that I've brought into cultivation. It's a shorter, stouter version of its commonly available European cousin, solitary clematis (Clematis integrifolia). Both are nonvining herbaceous plants that form tight clumps and get better with age. The sugarbowls clematis growing in the foothills around Fort Collins tend to be very hairy both in foliage and flower. Those that grow higher in the foothills, near Evergreen, Colorado, have smoother foliage and flowers. As you head into Colorado's southern foothills, they are very different altogether. The foliage is quite blue in color, with wider leaflets; the flower shape is less bell-like and more turbinate. Because of these obvious differences from the general species, some botanists have classified these as a separate species, C. scottii (see below).
As a nurseryman, I feel very fortunate to be able to live in this region, where the high plains meet the mountains, creating a melting pot of terrain and plants. I'm able to interact with such geographical and floral variety—first as a curious botanist, and then as a patient horticulturist.
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