Note: Do not rely on this information. It is very old.
Jacob's LadderJacob's Ladder, or Greek Valerian, Polemonium caeruleum, giving its name to the order Polemoniaoeae, is a herbaceous perennial, native to the North of England, and commonly grown in gardens, sometimes with variegated leaves. It grows about a foot high, with hardly branched stems, scattered pinnate leaves, and numerous shortly-stalked blue or white pentamerous flowers, nearly an inch across.
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