Content Detail

Jacob’s ladder is a sprawling perennial that produces blue-violet blooms in the spring. It is effective in cottage gardens, native gardens, wildflower gardens, beds, and borders in full sun and well-draining soils. This species is native to the Chicago region according to Swink and Wilhelm’s Plants of the Chicago Region and current research.

  • Family (English) Phlox
  • Family (botanic) Polemoniaceae
  • Tree or plant type Perennial
  • Native locale Chicago area, Illinois, North America
  • Size range Medium plant (12-24 inches)
  • Light exposure Full sun (6 hrs direct light daily), Partial sun / shade (4-6 hrs light daily), Full shade (4 hrs or less of light daily)
  • Hardiness zones Zone 3, Zone 4, Zone 5 (Northern Illinois), Zone 6 (City of Chicago), Zone 7, Zone 8
  • Soil preference Moist, well-drained soil
  • Tolerances Occasional flooding
  • Season of interest mid spring, late spring, early summer
  • Flower color and fragrance Blue, Purple
  • Shape or form Mounded, Upright
  • Growth rate Moderate
  • Wildlife Butterflies, Insect pollinators

Size and method of spreading:

Jacob’s ladder often matures to a height and spread of 1 to 2 feet. Plants spread by self-seeding and producing offsets from underground stem structures (rhizomes). 

Native geographic location and habitat: (include C-value if appropriate)

Jacob’s ladder has a native range that includes the Eastern and Central United States. C-Value: 8.

Attracts birds or pollinators: 

Jacob’s ladder attracts a number of bee species, including an andrenid bee that specializes in pollinating Jacob’s ladder. Bee flies, butterflies, skippers, and moths are also attracted to Jacob’s ladder. 

Leaf description:

What appears to be the individual leaves of Jacob’s ladder are actually leaflets that make up a larger, approximately 8-inch compound leaf. The compound leaves occur in an alternate arrangement on the stems. The five to 15 leaflets resemble a feather in their arrangement, with a single leaflet at the tip (odd-pinnately compound). They taper at both ends with the widest portion near the center (elliptic), have smooth edges (entire margins), are medium green in color, and directly attach to the center stalk (rachis). 

Flower description:

Jacob’s ladder has light to medium blue-violet, bell-shaped flowers that grow in loose, nodding clusters. Each flower has a tubular, reddish, leaflike structure (calyx) with five triangular lobes that surround the five ovate petals with slightly wavy edges. When the petals open, the flower has an approximate diameter of two-thirds of an inch. Protruding from the center of the petals are five long stamens with widened tops that bear pollen (anthers), and one long center structure (female pistil) that splits into three at the tip (three-parted style). Jacob’s ladder flowers grow on the terminal ends of the upper stems and on long stems (peduncles) that sprout from the axils of upper leaves. The branched inflorescences (panicles) mature upwards from the bottom. 

Fruit description:

The fruits of Jacob’s ladder are dry, divided into three cells, and split open when they have matured (capsules). They grow inside of the persistent calyx.

Plant Care:

Plant in full sun to full shade in moist, well-drained soil. Jacob’s ladder can be divided in late summer. Deadheading can reduce self-seeding and encourage continuous blooming. 

List of pests, diseases, and tolerances:

No major issues with pests and disease affect Jacob’s ladder.

Donate

Your support is vital to the Arboretum, where the power of trees makes a positive impact on people’s lives.

Make a gift