Larchleaf Penstemon Plant Care
Penstemon laricifolius Hook. & Arn.
Updated · Sources · How we source care data
Penstemon laricifolius, the larchleaf penstemon, is a small herbaceous plant from the northern Rocky Mountain states of Montana, Wyoming, and Colorado. It grows in a form like a small tuft of grass and has very narrow leaves.
Every 7–10 days
Full sun to part shade
50–80°F
40–70%
At a glance
How do you care for Larchleaf Penstemon?
Water Larchleaf Penstemon every 7–10 days, letting the top layer of soil dry out between waterings, and give it full sun to part shade. It prefers temperatures of 50–80°F (10–27°C) and 40–70% humidity. Fertilize it every 6 months during the growing season.
What Is the Larchleaf Penstemon?
Larchleaf Penstemon (Penstemon laricifolius) belongs to the Plantaginaceae family within the Penstemon genus. Larchleaf Penstemon is also known as Larch-leaf Penstemon.
Larchleaf Penstemon displays an upright, clumping perennial growth habit, reaching up to 2 ft tall with a spread of approximately 1.5 ft. Larchleaf Penstemon produces tubular flowers in shades of red, pink, purple, or blue.
Leaf size: approximately 4 inches.
How Often Should You Water a Larchleaf Penstemon?
Penstemon laricifolius requires watering every 7–10 days. Allow the top layer of soil to dry between waterings to prevent root rot. Reduce watering frequency during winter when growth slows.
Watering Frequency
Every 7–10 days
Let soil partially dry between waterings
What Light Does the Larchleaf Penstemon Need?
Larchleaf Penstemon thrives in full sun to part shade.
Light Requirement
Full sun to part shade
What Temperature and Humidity Does the Larchleaf Penstemon Prefer?
Penstemon laricifolius grows best at temperatures of 50–80°F. Larchleaf Penstemon prefers humidity levels of 40–70%.
Temperature
50–80°F
Humidity
40–70%
What Soil Mix Works Best for a Larchleaf Penstemon?
Well-draining sandy loam with added organic matter for moisture retention. Good drainage is essential for Larchleaf Penstemon to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Larchleaf Penstemon?
Feed Larchleaf Penstemon every 6 months during the growing season (spring and summer) with a balanced fertilizer diluted to the strength on the label.
Pause feeding in autumn and winter, when growth slows, and never fertilize dry soil — water first.
Fertilizing
Every 6 months
During the growing season
The PlantoScan app can remind you when to water and when to fertilize each plant.
How Do You Repot a Larchleaf Penstemon?
Repot every 2-3 years in early spring. Choose a pot one size larger than the current container, and ensure it has drainage holes to allow excess water to escape.
How Do You Propagate a Larchleaf Penstemon?
Larchleaf Penstemon can be propagated through seeds, stem cuttings. Similar propagation techniques also apply to foxglove beardtongue plant care, which shares the same genus.
Is the Larchleaf Penstemon Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Larchleaf Penstemon, so we can't confirm whether it is safe for cats and dogs. Keep pets from chewing it as a precaution.
This is a general caution, not veterinary or medical advice. If your pet ate a plant, contact your vet or animal poison control.
See all plants toxic to cats and plants toxic to dogs.
What Pests and Diseases Affect the Larchleaf Penstemon?
Larchleaf Penstemon is susceptible to aphids, spider mites, powdery mildew. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.
Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.
What USDA Hardiness Zone Does the Larchleaf Penstemon Need?
Larchleaf Penstemon grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. In cooler regions, grow Larchleaf Penstemon as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 12a
Keep exploring plants
Larchleaf Penstemon is one of many species covered in the complete plant care and identification guide, which groups plants by genus, attribute, and popularity.
It belongs to the Penstemon genus — compare its care with other Penstemon species on PlantoScan.
Penstemon is part of the Plantaginaceae plant family — browse all Plantaginaceae genera and species.
Larchleaf Penstemon thrives in bright light and direct sun — see other bright-light plants.
More Penstemon Species
Other Penstemon species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Penstemon laricifolius Hook. & Arn., family Plantaginaceae (first published in Bot. Beechey Voy. : 376 (1839)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Larchleaf Penstemon, so we can't confirm whether it is safe for cats and dogs. Checked against the ASPCA plant list; any other toxicity note on this page comes from PlantoScan's plant database.
- Hardiness zone: USDA Zone 12a, calculated from the plant's minimum temperature.
- Care values(watering, light, temperature, humidity, soil, fertilizing): PlantoScan's plant database, filtered by automatic plausibility checks — values that fail them are hidden. How we source and check plant data.
Spotted a mistake? Email info@upvision.media with the page link — we check and correct reported errors.
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