Agave (century plants) are in the top tier of my favorite plants. I enjoy them for their incredible geometric symmetry, their ornamental yet fearsome spination and the remarkable impact their sculptural forms have on the landscape, especially the larger growing species.
The genus is native to North America with the bulk of its species to be found in Mexico. But they also range northward into the southwestern US finding homes in some very cold, higher elevation terrain. Two of my favorite species, Agave parryi, Flagstaff form and Agave utahensis v. kaibabensis are reliably cold hardy to USDA zone 5a given the right growing conditions. Having sought these two species in habitat to collect seed, I have developed a special appreciation for these two plants, especially given the extreme harshness of their environments.
Agave parryi, Flagstaff form is found on the high plateau in several locations south and west of the city of Flagstaff. Flagstaff is a very cold, high elevation location (USDA zone 5a or 4b) with erratic weather and a short growing season. The parryi population where I found the seed I grow, is located at 6,800 ft. elevation a few miles south of the city. This colony is found on the south-facing flanks of a gentle hill with the incredible Oak Creek Canyon visible to the south. Growing in a mixture of clay and black volcanic rock, I found numerous plants, with mature silver rosettes up to 3 ft. in width!
Here, Agave parryi is scattered among stunted Ponderosa pine, Mountain Mahogany (Cercocarpus montanus) and the most remarkable specimens of Alligator juniper (Juniperus deppeana) I’ve ever seen. These ancient trees were only about 12-15 ft. tall but had trucks easily 3 ft. in diameter. The area is so exposed to the harsh sun and wind, dry summers and wickedly cold winters, that all the plants are supremely challenged to grow there.
About 60 miles to the north as the crow flies, passing over Flagstaff and the snowy 12,000+ ft. peaks of the San Francisco Mts. can be found the habitat of another of Arizona’s most remarkable Agave, species, utahensis v. kaibabensis. It is growing on the rolling plains (elevation 5,000 ft.) through which the deepening canyon of the Little Colorado River winds its way west to join the Grand Canyon. I was amazed by the size of the mature var. kaibabesis plants; the stout, rather narrow olive green leaves making rosettes 30 inches wide.
This is nearly twice as large as any other A. utahensis form. Never abundant, theseAgave plants are scattered among low growing sage, Ephedra and other shrubs. As I was walking across the hills, I made a startling discovery, finding one huge cluster after another of the rare Echinocactus xeranthemoides scattered through the sage. These cacti are clearly quite old as it takes many, many years (under the best of conditions) for this species to mature. The largest multi-headed specimens are growing out of rock ledges looking down over the Little Colorado’s vertical canyon walls. Finding these incredible Echinocactus and Agave specimens thriving in this incredibly harsh, scenic country was a thrill I’ll never forget.