Photo: no rights reservedCC0 1.0via iNaturalist
Sharp-flowered Jacob's Ladder Plant Care
Polemonium acutiflorum Willd.
Updated · Sources · How we source care data
Polemonium acutiflorum, native to North America, is easily identified by its striking blue bell-shaped flowers that bloom in late spring. This plant's delicate, fern-like foliage is a favorite among collectors for its unique appearance and ability to attract butterflies and hummingbirds to the garden.
Every 7–10 days
Partial shade to full shade
50–75°F
40–70%
At a glance
How do you care for Sharp-flowered Jacob's Ladder?
Water Sharp-flowered Jacob's Ladder every 7–10 days, letting the top layer of soil dry out between waterings, and give it partial shade to full shade. It prefers temperatures of 50–75°F (10–24°C) and 40–70% humidity. Fertilize it every 6 months during the growing season.
Where Is the Sharp-flowered Jacob's Ladder Native To?
What Is the Sharp-flowered Jacob's Ladder?
Sharp-flowered Jacob's Ladder (Polemonium acutiflorum) belongs to the Polemoniaceae family within the Polemonium genus. Sharp-flowered Jacob's Ladder is native to western Canada and Alaska. Sharp-flowered Jacob's Ladder is also known as Jacob's Ladder, Skypole.
Sharp-flowered Jacob's Ladder displays a clumping perennial growth habit, reaching up to 1.5 ft tall with a spread of approximately 1 ft. Sharp-flowered Jacob's Ladder produces clusters of tubular, bell-shaped flowers in shades of blue, pink, or white.
Leaf size: approximately 4 inches.
How Often Should You Water a Sharp-flowered Jacob's Ladder?
Polemonium acutiflorum 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 Sharp-flowered Jacob's Ladder Need?
Sharp-flowered Jacob's Ladder thrives in partial shade to full shade. The optimal light range is 100–1,000 lux. Avoid placing Sharp-flowered Jacob's Ladder in direct, harsh sunlight for extended periods, as this can scorch the foliage.
Light Requirement
Partial shade to full shade
100–1,000 lux
What Temperature and Humidity Does the Sharp-flowered Jacob's Ladder Prefer?
Polemonium acutiflorum grows best at temperatures of 50–75°F. Sharp-flowered Jacob's Ladder prefers humidity levels of 40–70%.
Temperature
50–75°F
Humidity
40–70%
What Soil Mix Works Best for a Sharp-flowered Jacob's Ladder?
Moist, well-draining soil with high organic content. Good drainage is essential for Sharp-flowered Jacob's Ladder to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Sharp-flowered Jacob's Ladder?
Feed Sharp-flowered Jacob's Ladder 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 Sharp-flowered Jacob's Ladder?
Divide clumps 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 Sharp-flowered Jacob's Ladder?
Sharp-flowered Jacob's Ladder can be propagated through seeds, division. Similar propagation techniques also apply to jacob's ladder plant care, which shares the same genus.
Is the Sharp-flowered Jacob's Ladder Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Sharp-flowered Jacob's Ladder, 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 Sharp-flowered Jacob's Ladder?
Sharp-flowered Jacob's Ladder 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 Sharp-flowered Jacob's Ladder Need?
Sharp-flowered Jacob's Ladder grows outdoors in USDA Zone 2a – 6b. It survives winters down to planting zone 2a. Sharp-flowered Jacob's Ladder is native to western Canada and Alaska.
Hardiness Zone
Zone 2a – 6b
Keep exploring plants
Sharp-flowered Jacob's Ladder 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 Polemonium genus — compare its care with other Polemonium species on PlantoScan.
Polemonium is part of the Polemoniaceae plant family — browse all Polemoniaceae genera and species.
Sharp-flowered Jacob's Ladder copes with lower light than most plants — browse the full list of low-light plants.
More Polemonium Species
Other Polemonium species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Polemonium acutiflorum Willd., family Polemoniaceae (first published in Syst. Veg., ed. 15 bis [Roemer & Schultes] 4: 792. 1819) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Sharp-flowered Jacob's Ladder, 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.
- Photo: Public domain, CC0 1.0, iNaturalist — original.
- Hardiness zone: USDA Zone 2a – 6b, estimated from the plant's typical growing conditions.
- 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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