This prostrate perennial evening prim-rose is becoming increasingly popular, and rightly so. A first-rate introduction from the United States, it has astonishingly large and conspicuousfor its size, lemon-yellow trumpets up to 4 inches (10 cm) across on diminutive stalks rising from a mat oflong, narrow, pointed . It flowers for many weeks through the summer and is a fine plant for the front of a sunny border, or for a rock garden. Space the plants 18 inches (45 cm) apart in any good garden soil.
In the border, you need at least five plants to make a show, and they look particularly well illuminating plants of dusky blue. Try a patch in front of purple-leaved sage (Salvia officinalis ‘Pur-purascens’), or Salvia x superba, with spires of purple-blue labiate flowers which provide a contrast of form as well as colour. The area covered by the Oenothera should be labelled in late autumn, for the plant dies down to the last scrap ofand can easily be forked over and lost.
Gardeners who grow Oenothera mis-souriensis differ in their observation of its flowering timetable. Some say it is a true evening primrose, others that it flowers all day. 1 myself have seen it in many gardens fully open at noon.