Jacob’s Ladder: Regal Shade-Blooming Perennial

POLEMONIUM CAERULEUM

Jacob’s ladder, also known as Polemonium caeruleum (var. spelling coeruleum), is a hardy perennial herb of the Polemoniaceae family that includes phlox and gilia.

Add bright blue Jacob's ladder to your landscape for showstopping color: https://gardenerspath.com/plants/flowers/jacobs-ladder/ ‎

It seems to have come from Europe as an ornamental, seeded beyond its borders, and naturalized here. And, while there is evidence to suggest that it was used in medicinal applications in the past, P. caeruleum is not generally used as an herb today.

Other common names include charity, and Greek valerian, not to be confused with the “true” valerian plant, Valeriana officinalis.

Brighten up a shady area by planting bright blue Jacob's ladder: https://gardenerspath.com/plants/flowers/jacobs-ladder/ ‎

And to further muddy the waters, this plant is often mistaken for P. reptans, a U.S. native also called Jacob’s ladder, as well as false Jacob’s ladder, creeping Jacob’s ladder, American Greek valerian, and abscess root. This variety is still used in herbal preparations.

Majestic in Blue

The upright stems of P. caeruleum rise regally, often to a height of three feet. Wispy leaves alternate, resembling the rungs of a ladder.

Brighten up shady spots with colorful Jacob's ladder, a European import: https://gardenerspath.com/plants/flowers/jacobs-ladder/ ‎

The petals of its clustered blossoms are a brilliant blue, a gorgeous example of nature’s rare blue flowers. Bright yellow stamens provide striking contrast.

P. caeruleum is a late spring to early summer bloomer. Like the hosta, it thrives in shade where there is rich, well-drained soil, and makes a great understory plant beneath trees.

Given the opportunity to go to seed, it will naturalize on your property, returning in greater quantity each year.

Polemonium caeruleum Plant Facts

  • Blooms spring to early summer
  • Blue
  • Introduced
  • Naturalizes readily, invasive in some states
  • Performs best in cooler regions
  • Rich, well-drained soil, average moisture
  • Self-sows
  • Shade to partial shade
  • Up to three feet in height
  • Zones 4 to 8

Where to Buy

P. caeruleum seeds are available on Amazon from Everwilde Farms.

Jacob’s Ladder Native Wildflower Seeds

Each package contains 100 seeds.

Colorful Sentries

P. caeruleum is a striking flower that invigorates shady areas.

Shade-loving Jacob's ladder adds a spot of bright color to otherwise dark areas | GardenersPath.com

Plant it along stockade fences, to brighten the shadows they cast, and add structure to shorter plants arranged in the foreground.

How about welcoming visitors to your outdoor living space with tall spikes of brilliant blue flanking your garden gates?

For more ideas on bringing color into shady landscapes, see our article Choosing the Perfect Flowering Perennials: 5 for Your Shade Garden.

How have you added texture, color, and dimension to your gardens with shade-blooming perennials? Tell us in the comments section below.


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A collage of photos showing different views of blue Jacob's Ladder flowers in bloom.

Product photo via Everwilde Farms. Uncredited photos: Shutterstock.

About Nan Schiller

Nan Schiller is a writer with deep roots in the soil of southeastern Pennsylvania. Her background includes landscape and floral design, a BS in business from Villanova University, and a Certificate of Merit in floral design from Longwood Gardens. An advocate of organic gardening with native plants, she’s always got dirt under her nails and freckles on her nose. With wit and hopefully some wisdom, she shares what she’s learned and is always ready to dig into a new project!

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Snehi Kulkarni
Snehi Kulkarni (@guest_6286)
5 months ago

Hi Nan,
I am just starting with a little gardening and have bought Jacob’s ladder plant. I was wondering if I can plant a tassel fern with it in the same pot?

Nan Schiller
Nan Schiller (@rellihcsnan8)
Member
Reply to  Snehi Kulkarni
5 months ago

Hello Snehi –
We’re so glad you have taken up gardening! The two plants you have chosen are likely to be quite compatible, as both like a shady placement with moist, organically-rich soil that drains well and is on the acidic side. Best of luck!

Snehi Kulkarni
Snehi Kulkarni (@guest_6341)
Reply to  Nan Schiller
5 months ago

Thank you so much Nan.. I am a little overwhelmed with the gardening stuff since I bought a lot plants for the first time.. I have a bag of potting soil.. would you recommend anything more.. I do have liquid fertilizer as well.. would love to get tips on potting.. also can I keep these plants inside the house with Indirect sunlight? Please let me know

Snehi Kulkarni
Snehi Kulkarni (@guest_6792)
Reply to  Snehi Kulkarni
5 months ago

Hi Nan, can you please let me know your thoughts on the above? Thank you!

Snehi Kulkarni
Snehi Kulkarni (@guest_6797)
Reply to  Nan Schiller
5 months ago

Thank you! One more question: How do I make the soil acidic?

Nan Schiller
Nan Schiller (@rellihcsnan)
Admin
Member
Reply to  Snehi Kulkarni
5 months ago

The potting medium should meet the low threshold for acidity and be adequate.

Snehi Kulkarni
Snehi Kulkarni (@guest_6801)
Reply to  Nan Schiller
5 months ago

You mean the potting soil itself?

Allison Sidhu
Allison Sidhu (@allison-sidhu)
Admin
Noble Member
Reply to  Snehi Kulkarni
5 months ago

Yes, exactly. Jacob’s ladder can do well in a variety of soil types, but it prefers soil that is neutral to slightly acidic, about 6.0-7.0. Amendments like peat can acidify the soil, and you can check your soil’s pH if you like with pH paper or a soil test.

Val
Val (@guest_6647)
5 months ago

I planted Jacobs ladder 2 summers ago. The first summer it was beautiful. The second summer it returned and looked ok. This year I have nothing. It was planted in a semi shady spot with some morning sun. What happened?