Pink evening primrose
Oenothera speciosa · Onagraceae
📷 ZooFari · CC BY-SA 3.0
The gardener's calendar
Pink evening primrose is in full bloom: enjoy it, watch watering in hot weather and let spent flowers feed pollinators before pruning.
ID card
- Scientific name
- Oenothera speciosa
- Family
- Onagraceae
- Plant type
- Herbaceous perennial
- Adult height
- 60 cm
- Flowering
- May to September
- Foliage
- Deciduous
- Hardiness
- Hardy to -15°C
- Origin
- North and Central America
✓ Taxonomy verifiedSource: AI estimate · hardiness: reliability medium.
Expert tips
The key tip
Plant in light, well-draining soil (gravelly is ideal), in very bright exposure. A light compost application in spring is enough; avoid rich soils or waterlogged conditions.
The common mistake
Planting in rich soil and watering regularly in competition with other plants: it gets smothered, becomes an untidy shrub, flowers poorly or turns sickly.
The pro's trick
Sow seeds that have fallen naturally the previous autumn: they germinate in March without effort, and seedlings are more vigorous than those in pots.
Care
Exposure
Oenothera speciosa demands full sun exposure to offer its most beautiful flowering. Count on a minimum of 6 hours of direct sunlight per day. A slightly shaded location in very hot climates can be tolerable, but will reduce flower production.
Watering
Water needs are very moderate. Water regularly after planting, then gradually reduce watering once established. During the growing season (spring-summer), weekly watering is sufficient. The plant tolerates drought well; avoid excess moisture which causes root rot.
Soil
Oenothera prefers well-drained, light and undemanding soil. Sandy or gravelly soils suit it perfectly. Avoid heavy soils or those that are constantly wet. Adding potting soil or compost at planting time is enough; the plant doesn't require high fertility.
Fertilizing
No fertilizer is necessary if the soil was enriched at planting time. In case of poor flowering, a balanced fertilizer diluted in spring can boost growth. Avoid excess nitrogen which promotes foliage at the expense of flowers.
Pruning and cleanup
Remove spent flowers regularly to extend flowering. In late winter or early spring, cut the plant back to 15-20 cm from the ground to rejuvenate the clump. Remove dead or damaged stems as they appear.
Pests and diseases
Oenothera speciosa is not very prone to diseases. Powdery mildew can appear in very humid conditions; prefer direct rain to wetting the foliage. No major pests threaten it. Good air circulation and well-drained soil prevent most problems.
Did you know?
Oenothera speciosa is nicknamed 'Evening Rose' or 'Four O'Clock Flower' because its pale pink flowers typically open late in the afternoon and close by morning; this spectacular phenomenon has captivated botanists since its introduction to Europe in the 18th century. The genus Oenothera literally means 'wine buyer' in ancient Greek, because it was believed that the roots gave flavor to wine.
Where to buy it
Plant in spring or early autumn, avoiding spells of intense heat. Pick a plant with healthy foliage and roots that are not exposed. Best time: March, April, May, September.
Add this plant to my garden →Plants from the same family
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- Evening primroseOenothera fruticosa
- Bolivian fuchsiaFuchsia boliviana
- ClockweedOenothera lindheimeri
- Fuchsia regiaFuchsia regia
Tips generated and checked by Viridia — adapt them to your local climate.