Jacobs ladder plant (Polemonium caeruleum) profile

Written by Maggie

Apr 06 2021

Jacobs ladder plant (Polemonium caeruleum) profile

Jacob's ladder (Polemonium caeruleum) belongs to Jacob's ladder family, perennial herbs. Plant height is 30 ~ 50 cm; Stem is erect; Basal leaves are long petiolate; Cauline leaves are alternate, singular pinnate compound leaves, leaflets 11 to 21, ovate-lanceolate, entire. Panicle is terminal; Pedicels and sepals are with glandular hairs; Calyx is campanulate, 5-lobed; Corolla is 5-lobed, blue-purple; Capsule is round.Jacob's ladder is born in wet grassland, mountain gullies, shrubbery, China's Inner Mongolia, Heilongjiang and other places are distributed. Jacob's ladder can be used as medicine, has the effect of expectorant, hemostasis, sedation, treatment of acute and chronic bronchitis, gastric ulcer bleeding, cough and so on.

Jacob's ladder picture

Jacob's ladder

Jacob's ladder info

Botanical Name Polemonium caeruleum
Common Names Jacob's ladder
Plant Type Herbaceous perennial flower
Sun Part shade to full shade
Hardiness Zones 3 to 8 (USDA)
Flower color Mostly blue and purple; white, pink, and yellow cultivars also available
Native Area Northern Asia, Europe; has naturalized in Eastern North America
Mature size 12 to 24 inches tall; 12- to 24-inches spread

Morphological characteristics of Jacob's ladder


Jacob's ladder is a perennial herb, roots prostrate, terete, fibrous. Stems are erect, 0.5-1 m tall, glabrous or pubescent.


Jacob's ladder is alternate compound leaves pinnate, lower stem leaves up to 20 cm long, upper stem leaves 7 -- 14 cm long, alternate leaflets, 11 -- 21, ovate to lanceolate, 1.5 -- 4 cm long, 0.5 -- 1.4 cm wide, apex acute or acuminate, base subrounded, entire, pubescent or subglabrous on both sides, without petioles; Petiole is 1.5-8 cm long, proximally long, distally short petiole or sessile, sparsely pubescent or subglabrous with leaf axis.


Jacob's ladder is cyme panicle terminal or upper leaf axillary, sparse and many flowers; Pedicels are 3 -- 5 (-10) mm long, with pedicels densely short or sparsely long glandular hairs; Calyx is campanulate, 5-8 mm long, short or sparsely glandular-hairy, lobes long ovate, oblong or ovate-lanceolate, apex acute or obtuse, sparsely obtuse, nearly as long as calyx tube; Corolla is purplish-blue, campanulate, 1-1.8 cm long, lobes obovate, apex rounded or occasionally tapering or slightly acute, margin sparsely or densely ciliate or malt accented; Stamens of Jacob's ladder are borne above the base of corolla tube, usually as long as corolla, anthers ovoid, filaments clustered at the base of yellow-white pubescent; Ovary is globose, stigma slightly protruding beyond the corolla.


The capsule of Jacob's ladder is ovate, 5 -- 7 mm long. Seed is brown, fusiform, 3 -- 3.5 mm long, seed coat with expandable mucous cells, membranous dry posteriorly like seeds winged.

The ecological habits of Jacob's ladder

Jacob's ladder is born in the elevation of (1000-)1700-3700m hillside grass, valley sparse forest, roadside thickets and stream wetland. 

Jacob's ladder was born on a sunny slope with wet grass.

How to grow and care for Jacob's ladder


Jacob's ladder flowers opt for partial or dappled shade. Varieties with darkish inexperienced leaves can manage extra direct solar than the variegated varieties, so lengthy as the soil is stored persistently moist.


Plant Jacob's ladder in loose, rich, well-draining soil that will continue to be moist however now not wet. It is extra fussy about moisture than about soil pH however does pleasant with a rather impartial or barely acidic soil pH.


Jacob's ladder flora that acquires normal watering will bloom longer and continue to be alluring into summer. Water frequently to preserve medium moisture levels, however, keep away from soggy conditions. During dry periods, you might also want to water greater regularly to hold the vegetation lush.

Temperature and humidity

Jacob's ladder prefers a quite cool summer season climate, and it can succumb to excessive warmness in heat southern gardens. Very humid prerequisites can convey on-leaf spot fungal illnesses or powdery mildew.


Polemonium caeruleum is a long-lived perennial in the proper prerequisites and if it is fed properly. Give the vegetation a enhance in early spring with a dose of balanced fertilizer as the new increase is emerging. Feed them once more as soon as the dwindled flora has been reducing back.


In general, Jacob's ladder requires minimal maintenance. Once the flora end blooming, reduce the Flower stalks returned to the plant's base to motivate repeat blooms. If the foliage starts offevolved to appear tattered, it can additionally be reduce returned and cleaned up. A new boom will change the trimmed foliage.

Jacob's Ladder

Propagating Jacob's ladder

Divide mature Jacob's ladder flowers each and every two to 4 years or they will begin to die out in the center. They divide most without problems and efficaciously in early spring. Carefully elevate and separate the basal rosettes, replant, and water well.

Growing Jacob's ladder from seeds

If you already have Jacob's ladder plant, it will self-seed on its personal from seeds dropped from flower heads. You can additionally gather the seeds to replant elsewhere. Jacob's ladder can be direct seeded in both spring or fall. Loosely cowl the seed with soil, then water. Keep the soil moist, and be positive to mark the spot so that you do now not disturb it.

To begin seed indoors, sow two months earlier than your closing frost date if you favor to transplant in spring, or sow in mid-summer if you prefer to transplant in the fall. The seeds take up to a month to germinate and ought to be stored moist till then. Transplant exterior in spring simply earlier than your ultimate frost date, or in early to mid-fall.

Varieties of Jacob's ladder

Look for these sorts of Jacob's ladder for your garden:

Polemonium caeruleum' Album' has white flowers.

P. caeruleum 'Bambino Blue' elements lovely mild blue flowers.

P. caeruleum 'Snow and Sapphires' has variegated leaves and blue flowers; it is truly hardier than the comparable Brise d'Anjou.

P. reptans 'Stairway to Heaven' well-knownshows blue plants on variegated foliage that blushes red in cool weather.

Disease control of Jacob's ladder

Jacob's ladder insect pests are relatively few, if found disease plants should be promptly pulled outburned or buried, at the same time using 50% methyl tobujin 600 times liquid spray, for insect pests, can be used Lesoate control.

The distribution area of Jacob's ladder

Jacob's ladder is manufactured in several provinces in Northeast China, Hebei, Shanxi, Inner Mongolia, Xinjiang and Northwest Yunnan.

Jacob's Ladder is distributed in temperate Europe, Asia and North America. 

Jacob's Ladder