Polemonium boreale (Northern Jacobs Ladder)

Extremely cold-hardy, Polemonium boreale (Northern Jacob's Ladder) is a compact perennial with creeping underground stems forming a low, bushy mound of alternate, basal green leaves with very short petioles. The pinnately compound leaves, each adorned with 13-23 leaflets, are covered with long woolly hairs. In late spring to early summer, it is smothered with a profusion of unpleasantly scented, small sky blue flowers, adorned with a yellow eye and white stamens. They are highly adapted to insect pollination. Excellent for rock gardens or in the front of borders.

• Grows up to 12 in. tall and wide (30 cm).
• Thrives in average, medium, well-drained soils in sun or part shade. Prefers a cool, moist soil with protection from the hot sun. Intolerant of high heat and humidity.
• Generally pest free. Keep an eye out for powdery mildews.
• Deadhead regularly. If becoming untidy, cut back by half in midsummer to rejuvenate.
• Native to most of the high arctic.