Wildflower/Perennial · Sonoran native
Firecracker Penstemon
Penstemon eatonii · Plantaginaceae
Also called: Eaton's Penstemon, Eaton's Firecracker, Scarlet Bugler
Firecracker Penstemon (Penstemon eatonii) is a low-water wildflower/perennial native to the Sonoran Desert region well suited to Tucson and the low desert. It's a moderate to fast-growing wildflower/perennial.
Firecracker Penstemon at a glance
- Water use
- Low (established)
- Sun
- Full sun to light afternoon shade
- Mature size
- 1-3 ft H x 1-2 ft W; flower spikes to ~3 ft
- Growth rate
- Moderate to fast
- Bloom
- Brilliant scarlet to orange-red, tubular flowers, Spring (in Tucson often February-June; can rebloom later, even sporadically year-round)
- Cold hardiness
- Cold hardy to at least 0-10 F (about USDA zones 4-9); more freeze-sensitive when in active bloom
- Soil
- Needs sharp drainage; sandy, gravelly, rocky, or decomposed-granite soils. Intolerant of soggy ground.
- Native range
- Native to the southwestern U.S. (Arizona, Utah, Nevada, California, Colorado, New Mexico) across the Great Basin, Colorado Plateau, and Mojave; in Arizona ranges from higher elevations near Flagstaff down to desert plantings in the low desert.
- Best used as
- Hummingbird gardens, Spring color accent, Native and xeriscape plantings, Rock gardens
- Wildlife
- One of the top hummingbird-attracting penstemons; the red tubular flowers are timed to spring hummingbird migration. Also visited by native bees and butterflies.
- Toxicity
- Non-toxic.
How to grow Firecracker Penstemon in Tucson & the low desert
Watering
Very drought tolerant once established; in Tucson water every 1-2 weeks through the cool season and bloom, then reduce sharply in summer. Overwatering, especially in heat, causes rot.
Fertilizer & nutrients
Low needs; prefers lean soil. Little or no fertilizer required; over-feeding shortens its life and causes flopping.
Pruning & care
Remove spent flower stalks after bloom to encourage rebloom and neaten the rosette; allow some seed set for reseeding. Cut back to basal foliage when stalks decline.
Notes
Among the most robust and drought-tolerant penstemons for the Southwest. Reseeds to perpetuate itself. The red flower color and early bloom make it a standout for pollinator and color plantings in the low desert.
Sources: Arizona-Sonora Desert Museum (Firecracker Penstemon plant sheet); USDA NRCS Plant Guide (Penstemon eatonii); University of Arizona Cooperative Extension; AMWUA / Water Use It Wisely