Hardiness: USDA Zone 3a: to -39.9 °C (-40 °F) USDA Zone 3b: to -37.2 °C (-35 °F) USDA Zone 4a: to -34.4 °C (-30 °F) USDA Zone 4b: to -31.6 °C (-25 °F) USDA Zone 5a: to -28.8 °C (-20 °F) USDA Zone 5b: to -26.1 °C (-15 °F) USDA Zone 6a: to -23.3 °C (-10 °F) USDA Zone 6b: to -20.5 °C (-5 °F) USDA Zone 7a: to -17.7 °C (0 °F) USDA Zone 7b: to -14.9 °C (5 °F) USDA Zone 8a: to -12.2 °C (10 °F) USDA Zone 8b: to -9.4 °C (15 °F)
Other details: Average Water Needs; Water regularly; do not overwater
Soil pH requirements: 6.6 to 7.5 (neutral) 7.6 to 7.8 (mildly alkaline) 7.9 to 8.5 (alkaline)
Patent Information: Non-patented
Propagation Methods: From herbaceous stem cuttings From seed; direct sow outdoors in fall From seed; winter sow in vented containers, coldframe or unheated greenhouse From seed; stratify if sowing indoors
Seed Collecting: Allow pods to dry on plant; break open to collect seeds Properly cleaned, seed can be successfully stored
On May 30, 2010, MiniPonyFarmer from Gilmer, TX (Zone 8b) wrote:
I ordered three of these from Bluestone and have been happy with their performance. The first year, I got only foliage, but all appeared healthy. I must have rearranged their full sun bed 3 times and moved them each time. They never missed a beat each time I moved them. In my blistering hot and humid East Texas location, these plants received almost no water, and no shade. Yet, they looked great. The second year, I moved them once again to a new location for design purposes. Again, these plants never even blinked and then sent up tall spikes with blooms. What gorgeous blooms! Bees love them! They are a vivid intense purple with a sheen of electric blue on the tiny trumpet/bell shaped flowers. The clump of foliage stays low and small, and the spikes are about 30" tall. I found that it was better to place them about 10" apart, more closely than you might expect. I ordered 6 more this month!
On Jan 17, 2005, LilyLover_UT from Ogden, UT (Zone 5b) wrote:
Rocky Mountain penstemon is very striking with its deep violet-blue flowers on tall stems. It's one of the easiest penstemons to grow, although it prefers well-drained soil. It attracts hummingbirds and beneficial insects.
Start the seeds indoors, and stratify them for best germination.
This plant has been said to grow in the following regions:
Wasilla, Alaska Colorado Springs, Colorado Denver, Colorado Edgewater, Colorado Hotchkiss, Colorado Kiowa, Colorado Parker, Colorado Indianapolis, Indiana Helena, Montana Carson City, Nevada Carnuel, New Mexico Las Cruces, New Mexico Ojo Amarillo, New Mexico Rodeo, New Mexico Elba, New York Pottersville, New York Elizabeth City, North Carolina , Texas Austin, Texas Copper Canyon, Texas Jolly, Texas Bluffdale, Utah Farr West, Utah Genola, Utah West Valley City, Utah Essex Junction, Vermont Leesburg, Virginia Kalama, Washington Bayfield, Wisconsin Johnstown, Wyoming Riverton, Wyoming