These Penstemons like 10 to 40 inches of rainfall without added water! They can tolerate a little water to get established. After that leave them alone! They actually like dry summers and generally arid conditions. They do not tolerate garden conditions well. Most do great with sages, buckwheats, and other dry loving plants. These Penstemons are not good for coastal areas or areas with high rainfall or humidity. If this is you go to:The California Penstemons that like MOIST conditions or plant Penstemon Margarita BOP.
This Penstemon is similar to Scarlet burglar but more cold
tolerant. The flower clusters are denser and the leaves are
rounder and less gray. It is also a good hummingbird plant. It
grows 2 to 3ft tall.
This Penstemon can grow at 8000ft. elevation but has also done ok in Los Angeles and along the desert edges.
Foothill Penstemon is very similar to Penstemon Margarita Bop but it likes drier conditions, is taller and the flowers are more lavender. This Penstemon does the best in full sun, with shade it looks leggy. It is cold tolerant to about -10 Deg. F.(as long as the day warms up) Foothill Penstemon grows about 2 ft tall and is fairly dense (but doesn't own a large pickup, sorry, that could describe so many folks besides this plant).
This pink showy Penstemon is a large Penstemon. It is a big hit with the hummingbirds. The flower color is hard to describe. It is very deep pink. It really stands out. It produces a mass of flowers in late spring. Desert Penstemon is very drought tolerant. It hasn't been watered since it was planted.
Showy Penstemon can reach 4 ft tall! It is very drought tolerant, thriving on our 15 inches of rainfall. It looks better in full sun, tending to get leggy when it is given shade.Showy Penstemon will tolerate clays, but commonly loves decomposed granite.