Known to gardeners as Jacob’s ladder, the Polemonium genus contains up to 40 species of flowering plants, most of which are native to the cool temperate regions of the Northern Hemisphere. They are mostly perennial plants growing to between 10–120cm tall, with bright green leaves divided into lance-shaped ‘leaflets’ arranged in pairs opposite to each other, resembling the rungs of a ladder (hence the common name). Mostly they produce flowers in shades of blue (sometimes pink or white) in the spring and summer. A few of them are fragrant. In general, Jacob’s Ladder prefer partial shade and a moist soil, but in the UK and northern Europe we expect that you should be fine to grow it in a position in full sun. Cut back Polemonium after flowering in late spring, and you may get a second flush of bloom. They look particularly good in association with Astilbe, Heuchera, Hosta and smaller ornamental grasses, such as Carex or Festuca!