Growing Rocky Mountain Penstemon Garden Seeds
- Taxonomy: Penstemon strictus
- Other Names: Beardtongue
- Seed Type: Perennial
- Sow Indoors or Outdoors: Rocky Mountain penstemon is easy to grow from seed and may be sown directly outside after final frost or late in fall for early spring blooms. For earliest blooming, start indoors 8 – 10 weeks prior to final frost. Germination occurs in 14 – 21 days with full lighting, then transplant to a sunny spot in the garden or keep as a potted and fragrant grow indoors near a window with full sun.
- Days to Maturity: 120 days
- Hardiness Zone: 4 - 9
- Planting Depth: 1/8”
- Plant Spacing: 18 – 24”
- Growth Habit: 12 – 30” tall bushy upright with a 24 – 36” spread covered in flirted stalks of 1” “snapdragon-like” blooms
- Soil Preference: Fertile, evenly moist, well-drained
- Light Preference: Full sun
- Diseases/Pests/Troubleshooting: Unlike its cousin, the snapdragon, Rocky Mountain penstemon is native to arid juniper forests of the American west and prefers hot conditions. Trim plants to provide proper air circulation and avoid overwatering as penstemon does not perform well in soggy and poorly drained soils. Penstemon has no serious pests or diseases but monitor regularly for aphids and white flies.
- Color: Rich leafy foliage with petals in shades of indigo and royal blue
Rocky Mountain penstemon is easy to grow from seed and may be sown directly outside after final frost or late in fall for early spring blooming. For earliest blooms, start Rocky Mountain penstemon seeds indoors 8 – 10 weeks prior to final frost. Germination occurs in 14 – 21 days with full lighting, then transplant to a sunny spot in the garden or keep as a potted and fragrant grow indoors near a window with full sun. For direct sowing, plant Rocky Mountain penstemon seeds ¼” deep and 18 – 24” apart in fertile, evenly moist, and well-drained soil in full sun. Unlike its cousin, the snapdragon, Rocky Mountain penstemon is native to arid juniper and pine forests of the American west and prefers warm, sunny climates. Trim plants to provide proper air circulation and avoid overwatering as penstemon does not perform well in soggy and poorly drained soils. Penstemon has no serious pests or diseases but monitor regularly for aphids and white flies. Rocky Mountain penstemon seeds mature in 120 days as 12 – 30” tall bushy uprights with a 24 – 36” spread bursting with stalks of 1” “snapdragon-like” blooms.
Penstemon strictus is native to the warm arid pine and juniper forests between southern Wyoming and Colorado down into New Mexico and Arizona. Rocky Mountain penstemon is sometimes loosely referred to as snapdragon since it is a member of the Plantaginaceae family or, better known as, the snapdragon family.