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.
Scarlet Bugler has gray foliage and bright red
flowers. Hummingbirds love this plant. It likes clean
bare soil with low fertility. It grows in the coast ranges from
beach sand to decomposed granite, clay loam and gravelly
sand. It can tolerate hot summer
temperatures regularly to 115 Deg F,, winter
temperatures to -15 Deg F or summer fog. Scarlet Bugler likes full
sun or part shade but will flower more in the sun.
The Penstemon flower spike is 2 to 3ft tall, while the foliage is a little clump at the base..
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.
Southern woodland Penstemon
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 tidy blue Penstemon was planted in our demonstration garden in full sun with no protection and is doing great on our 15 inches of rainfall. Western desert Penstemon is native to our deserts and grows right along side Joshua trees and up into the Pinyon pines. With its flowers this Penstemon is about 3 ft tall.
Penstemon pseudospectabilis, Desert penstemon
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.
Penstemon spectabilis, Showy Penstemon
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.