Garden Oracle / Drought and Heat Tolerant Gardening / Tucson - Phoenix - Arizona - California

Growing Penstemon baccharifolius:
Rock Penstemon

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Form: A subshrub with a woody base and herbaceous stems.
Lifespan: Perennial.
Leaf retention: Evergreen to 28°F if protected from wind.
Growth rate: Moderate to rapid.
Mature Size: 12-18" high and 6-12" wide.
Flowers: Cherry-red to pink, may be whitish inside, tubular, in clustered spikes.
Bloom: Spring into fall. For some cultivars, a single plant may bloom up to four months in favorable conditions.
Fruit: Seed capsule containing tiny seeds.
Leaves: Glossy green, thick, oval with small-toothed margins on the lower stem and lance-shaped with smooth margins on the upper stem. The leaves may turn purple in cold weather.
Stems: Herbaceous on a woody base, no thorns.
Roots: Should be shaded all day, especially afternoon shade. Tightly spaced large gravel can be used to provide shade.
Wildlife: Attracts hummingbirds. Browsed by mammals.
Toxic / Danger: No.
Origin: Texas and Mexico.

Cultivation and Uses
USDA hardiness zones: 8-10. This plant may die to the ground below 28°F. Provide winter wind protection in regions with freezes.
Heat tolerant: Yes.
Drought tolerant: Yes.
Sun: Full sun to part afternoon shade for the leaves and flowers. Provide all-day shade for the roots.
Water once established: Once or twice a month. This plant is susceptible to root rot. Avoid overwatering.
Soil: Very well drained, dry, ph 6.1-7.8 (slightly acidic to slightly alkaline).
Mulch: Decomposed granite (optional). Always use provide an additional means to shade its roots from the sun.
First Year Care: This plant can be slow to establish. It may not bloom until the second year even when transplanted from a pot.
Prune: After the last freeze, remove winter damage or cut it nearly to the ground. Pruning the oldest branches keeps it denser.
Litter: Low.
Propagation: Seed planted in the fall; cuttings of new growth taken in the spring.
Uses: Ornamental, hummingbird garden, rock garden.

Rock Penstemon is a member of the Penstemon and Plantain family (Plantaginaceae). It likes its head in the sun and its feet in the shade and can be found growing in steep rock faces in the wild. Place it inside a protected area to avoid browsing. This is one of the easiest to grow, and most hardy, penstemons for desert regions when it is in a well-drained, afternoon-shaded location.

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Penstemon baccharifolius: Rock Penstemon - flower

Penstemon baccharifolius: Rock Penstemon - flower

Penstemon baccharifolius: Rock Penstemon

Latest update: May, 2021
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