Plants of the Eloise Butler Wildflower Garden

The Polemonium genus covers a large number of plants commonly known as "Jacob's Ladder." Polemonium reptans, while still referred to as "Jacob's Ladder" is more correctly named "Greek Valerian" or "Spreading Jacob's Ladder" as it can root from the stems.

Spreading Jacob's Ladder is a native mostly erect perennial forb growing 8 to 20 inches high on slender stems that frequently recline. There is some branching near the top. Stems are light green but can be reddish green, usually smooth, with angled sides.

The leaves are alternate and pinnately-divided into 7 to 17 oblong leaflets, each leaflet up to 1-1/2 inches long. A terminal leaflet creates the odd number of leaflets. Leaflets are medium green in color, with smooth edges, usually no hair on the upper surface, and usually not stalked. The upper leaves within the the inflorescence usually have only 3 to 5 leaflets, sometimes just a simple leaf. The underside of the leaflet is paler in color with some fine hair.

The inflorescence is a loosely branched panicle with just a few flowers per branch, arising at the top of the stems and held above the leaves.

The flowers are bell shaped with 5 blue-violet petals that spread slightly. (White albinos are known to occur.) The calyx is light green, sometimes with reddish tints, sometimes with fine hair. Its five lobes are triangular. There are five stamens with whitish filaments and pale yellow anthers. There are not exserted - not longer than the petals. The single style is longer and has a 3-parted stigma.

Seed: Fertile flowers produce a dry 3-chambered seed capsule with about 3 seeds in each chamber. Seeds require 60 days of cold stratification for germination.

Habitat: Greek Valerian or Spreading Jacob's Ladder grows in the rich soils of open woods, slopes, shaded banks. While it may tolerate full sun, it will do best in light shade to dappled sun such as under a high tree canopy. For best bloom it needs soils that are moist to mesic. The stems may root if they lay on the ground. The root system is fibrous with a small crown. It also spreads by reseeding.

Names: The genus name Polemonium is a bit obscure but according to Stern (Ref. #37a) comes from the Greek pŏlĕmōniŏn which referred to an old medicinal plant thought to have a connection back to the Greek philosopher Polemon of Cappadocia. The species name, reptans, refers to having creeping or rooting stems. The name 'Jacob's Ladder' is an old biblical reference to the leaflets forming 'a ladder to heaven'. The author name for the plant classification - 'L.' refers to Carl Linnaeus (1707-1778), Swedish botanist and the developer of the binomial nomenclature of modern taxonomy.

Comparisons: Several species are similar to P. reptans. P. occidentale [photo below] and P. vanbruntiae have brighter flowers with stamens exserted beyond the petals which are wider spreading. The garden variety of Jacob's Ladder sometimes sold with the scientific name P. caeruleum and sometimes with the other scientific names and called "Greek Valerian" or "Jacob's Ladder" has fewer narrower leaves, blue flowers and seed capsules without stalks. These are not native species.