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Common Name: Jacob's Ladder
Polemonium caeruleum is a Perennial up to 0.40 metres tall.
It has medicinal uses.
Northern and central Europe, including Britain, to Siberia and the Caucasus.
Margins of woods and swamps, by streams, especially on turf and usually in limestone hills[
A very easily grown plant, it prefers a moist well-drained fertile soil in sun or semi-shade[
]. Dislikes damp or heavy soils[
], though it tolerates alkaline conditions[
Hardy to at least -20°c[
A polymorphic species, there are several sub-species[
] and many named forms[
Plants are fairly short-lived in cultivation unless they are divided regularly and moved to fresh soil[
]. They can self-sow to the point of nuisance, however[
] and will also survive when growing in lush grass[
Cats are strongly attracted by the smell of this plant and will frequently roll on it and injure it[
The herb is astringent and diaphoretic[
]. It was formerly used internally in the treatment of a wide range of conditions ranging from headaches to fevers and epilepsy[
]. The plant is harvested in the summer and dried for later use[
Seed - sow spring in a cold frame[
]. Another report says that the seed is best sown in a cold frame in the autumn[
]. When they are large enough to handle, prick the seedlings out into individual pots and plant them out in the summer.
Division in early spring or early autumn[
]. Larger divisions can be planted out direct into their permanent positions. We have found that it is better to pot up the smaller divisions and grow them on in light shade in a cold frame until they are well established before planting them out in late spring or early summer.