Ground covers, Perennials
There are some 250 species of penstemon. Most are native to the West, ranging from Canada into Mexico; some grow on the highest mountains, some in the desert, and others in forest glades, in foothills, on plains. A few are widely available, but most are sold only by specialists. Some of the perennials described here have woody-based stems, while others are herbaceous. Most species have narrowish, pointed leaves; those in basal foliage clump are larger, those on flower stems are smaller. Narrowly bell-shaped, lipped flowers (usually 3/4–1 1/2 in. long) are most commonly seen in bright reds and blues, but they also come in shades from soft pink through salmon and peach to deep rose, lilac, dark purple, white, and, rarely, yellow. Blossoms of some species attract hummingbirds.
Need fast drainage. Species in particular benefit from rock garden conditions. Usually short lived (3 or 4 years). Hybrids and selections tend to be easier to grow than wild species alongside regular garden plants; wild kinds may die quickly if given too-rich soil and too much water. In dry years or with restricted water, however, plants of wild species may thrive.Penstemon pinifolius
Native to southern New Mexico and Arizona. Woody-based growth to 1 1/2 ft. high and 2 ft. wide, with short, needlelike bright green leaves crowded along the stems. Red-orange summer flowers. For rock gardens and borders or as a small-scale groundcover. Good in dry gardens or regularly watered ones.
Native to southern Europe and the Caucasus. Compact, leafy, aggressive, spreading by volunteer seedlin...
From the Pyrenees. Forms wide, 8–12-in.-tall mats composed of 1–1 1/2-in., soft gray-green...
Plant is 1 ft. tall and 2 ft. wide; has lilac blooms and resists mildew.