Polemonium Species, Jacob's Ladder

Polemoniumcaeruleum

Family
Polemoniaceae (po-le-moh-nee-AY-see-ee)
Genus
Polemonium (po-le-MOH-nee-um)
Species
caeruleum (see-ROO-lee-um)
Synonym
Polemonium laxiflorum
Sun Exposure
Light Shade
Partial to Full Shade
Full Shade
Foliage
Herbaceous
Height
12-18 in. (30-45 cm)
18-24 in. (45-60 cm)
24-36 in. (60-90 cm)
Spacing
12-15 in. (30-38 cm)
Hardiness
USDA Zone 3a: to -39.9 °C (-40 °F)
USDA Zone 3b: to -37.2 °C (-35 °F)
USDA Zone 4a: to -34.4 °C (-30 °F)
USDA Zone 4b: to -31.6 °C (-25 °F)
USDA Zone 5a: to -28.8 °C (-20 °F)
USDA Zone 5b: to -26.1 °C (-15 °F)
USDA Zone 6a: to -23.3 °C (-10 °F)
USDA Zone 6b: to -20.5 °C (-5 °F)
USDA Zone 7a: to -17.7 °C (0 °F)
USDA Zone 7b: to -14.9 °C (5 °F)
Danger
N/A
Bloom Color
Dark Blue
Medium Purple
White/Near White
Bloom Time
Mid Summer
Other Details
Category
Perennials
Water Requirements
Requires consistently moist soil; do not let dry out between waterings
Foliage Color
Where to Grow
Bloom Characteristics
This plant is attractive to bees, butterflies and/or birds
Bloom Size
Other details
Soil pH requirements
6.1 to 6.5 (mildly acidic)
6.6 to 7.5 (neutral)
7.6 to 7.8 (mildly alkaline)
Patent Information
Non-patented
Propagation Methods
By dividing the rootball
From seed; sow indoors before last frost
From seed; direct sow after last frost
Seed Collecting
Bag seedheads to capture ripening seed
Wear gloves to protect hands when handling seeds
Properly cleaned, seed can be successfully stored
Regional

This plant is said to grow outdoors in the following regions:

Anchorage, Alaska(2 reports)

Bigelow, Arkansas

Salinas, California

Washington, District of Columbia

Cordele, Georgia

Galva, Illinois

Peoria, Illinois

Fishers, Indiana

Indianapolis, Indiana

Jeffersonville, Indiana

Gaithersburg, Maryland

Wellesley Hills, Massachusetts

Battle Creek, Michigan

Owosso, Michigan

Royal Oak, Michigan

Saginaw, Michigan

Hopkins, Minnesota

Osseo, Minnesota

Forsyth, Missouri

Piedmont, Missouri

Auburn, New Hampshire

Manchester, New Hampshire

Merrimack, New Hampshire

Egg Harbor Township, New Jersey

Chama, New Mexico

Alden, New York

Nineveh, New York

West Islip, New York

West Kill, New York

Pembina, North Dakota

Akron, Ohio

Cincinnati, Ohio

Wren, Ohio

MOUNT HOOD PARKDALE, Oregon

Portland, Oregon

Bellefonte, Pennsylvania

Chalfont, Pennsylvania

Lancaster, Pennsylvania

Philadelphia, Pennsylvania

Summerville, South Carolina

Knoxville, Tennessee

Viola, Tennessee

Montpelier, Vermont

CHIMACUM, Washington

Kalama, Washington

Langley, Washington

Olympia, Washington

Poulsbo, Washington

Ellsworth, Wisconsin

show all

Featured Videos

Gardener's Notes:

10
positives
4
neutrals
6
negatives
Sort By:
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K
Chama, NM | May 2016 | positive

Grows easily and self-sows in heavy clay soil beneath a Ponderosa Pine (there is a layer of peaty soil on top from the pine needles). One...Read More

V
Antioch, TN | July 2012 | negative

I also have tried growing this plant in TN with no success. 3 times I have tried growing this plant and they have all died.

M
Hopkins, MN (Zone 4a) | June 2012 | positive

I started with two of these, planted on the east side of my yard and shaded by a large shrub, and I have totally neglected them. They gr...Read More

W
Petersburg, VA | May 2010 | negative

In my Zone 7a garden, in Petersburg, Virginia, I have had this plant fail several times, in both solid and variegated leaf. I don't know...Read More

A
Philadelphia, PA | May 2010 | neutral

I grew this plant in Anchorage, Alaska, where it seeded aggressively. Pretty plant with hosta, yarrow and ferns, but I grew to hate it t...Read More

B
Lancaster, PA | March 2010 | positive

I agree that this plant can be a tough one to grow. I had no success growing it in clay soil. It just stayed small and some died. I mo...Read More

T
Woodbury, MN (Zone 4a) | June 2008 | positive

I grew two of these from seed. One didn't survive the summer in my clay soil, the other returned this spring with a vengence! I thought i...Read More

M
Winsted, CT | October 2007 | negative

Mine barely seems to survive but has come back 2 yrs in zone 6.
Even when it was healthy- the flowers are very small and not very ...Read More

G
(Zone 5a) | June 2006 | negative

I love the plant, but every one I've had died.

R
| May 2006 | positive

This plant grows well in semi shade. The plant I have is a self setter. I have no idea where it came from. It stands erect and has a heig...Read More

F
(Zone 8a) | May 2006 | positive

Lovely plant - we have this growing in moist, not well drained, clayish soil next to a Brunnera, and they're both thriving. And it's not ...Read More

E
E
Bigelow, AR | July 2005 | neutral

I bought one plant in early spring and it grew well for several months until the southern summer began. In spite of being planted in ligh...Read More

C
Wales, MA (Zone 6a) | April 2005 | negative

This plant loves my garden -- it's invasive, trying to run over well-established hostas, peonies, and herbs; I'm having a tough time kill...Read More

A
Anchorage, AK (Zone 4a) | September 2004 | positive

Self propagrates occasionally. Grows wild in parts of AK, and is a looked-for wild flower in the early spring. Grows on sunny mountain...Read More

C
West Kill, NY | September 2004 | positive

There was a white cultivar in my garden when I moved in. The flowers are a little weedy-looking and grow on very long stems--some over fi...Read More

P
P
North Tonawanda, NY (Zone 6a) | September 2004 | positive

Grows very easily from seed. I think every seed that I winter sowed germinated. Has grown steadily all summer. Didn't bloom the first ...Read More

C
Auburn, NH | May 2004 | negative

Four year old plant did not survive very cold winter which has frequent days and nights that hit between 0 and -20F. Not as hardy as not...Read More

S
Oklahoma City, OK (Zone 7a) | August 2002 | positive

Splendid choice for cutting gardens, border edgings and rock gardens. Brightens shady areas. Plant in a well-drained locatoin and water...Read More

L
L
(Zone 8a) | May 2002 | neutral

A handsome plant with long heads of hazy-blue showy flowers and finely divided foliage. When ripe, each anther bursts, releasing a mass o...Read More

C
Clarksville, TN (Zone 6b) | October 2001 | neutral

Grows wild in England. It is a woodland plant for the shaded garden or for naturalizing in moist, leafy soil.

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