Jacob's Ladder gets its name from the arrangement of its leaves – pairs of opposite leaflets resembling a ladder. In early summer, erect stems rise up from the bright green foliage carrying clusters of bell-shaped, lavender-blue flowers.

A cottage garden favourite, i>Polemonium caeruleum is happiest in partial shade, and looks equally at home in a wildlife garden setting or in grass. Although it is short-lived, it self-seeds freely.