Oenothera missouriensis - Evening Primrose

Oenothera missouriensis (macrocarpa) is a curious creeping evening primrose also known as the Missouri Evening Primrose. It is a perennial that thrives in sunny and dry soils, with a vibrant lemon yellow summer flowering. Its large ephemeral flowers, with a sweet scent, bloom in the evening and rest on a light green deciduous foliage, with visible white veins that contrast with short red stems. The large cups close around midday and fade into a beautiful red-orange hue. Over time, the plant spreads into beautiful carpets that remain unaffected by scorching heat, even in poor soil. Maintenance-free and worry-free, it beautifully accompanies all blue blooms.

Native to the central and southern United States, Oenothera missouriensis, is an almost stemless species belonging to the evening primrose family. It forms a rosette of large lanceolate leaves that will not exceed 15cm (6in) in height. This plant spreads laterally and over time forms broad carpets of 60cm (24in) or more. The flowering period takes place from June to August, depending on the climate, and covers the plant for two months with very large intense lemon yellow cups, with a crepe-like texture, 10cm (4in) wide. Each flower blooms in the evening amidst the leaves and closes the next day in the middle of the day, turning red-orange. This continuously renewing flowering mainly attracts butterflies, including a nocturnal sphinx. In late summer, the plant produces large winged fruits whose seeds easily germinate in light soil. In favuorable conditions, Oenothera missouriensis can sometimes become invasive.

Easy to cultivate and not demanding, the Missouri Evening Primrose thrives in poor, well-drained soils, even in dry summers. It loves sunny exposures and blends beautifully in a dry garden with lavender, Perovskia 'Blue Spire', or Nepeta racemosa to enhance their blue flowers with a vibrant yellow contrast. Its creeping habit and vigour allow it to quickly form a ground cover that requires little maintenance. This perennial that thrives in poor soils also thrives in rock gardens, alongside sunroses, Erigeron karvinskianus, Geranium sanguineum, Erodium, or California poppies. It can be planted on a wall, paired with blue Aubrietas and Campanula portenschlagiana. It can also be grown in pots or containers on a balcony.