Ludwigia grandiflora
Ludwigia grandiflora · Onagraceae
The gardener's calendar
Ideal time to plant ludwigia grandiflora: set it out when the soil is neither frozen nor waterlogged, and water generously as it establishes.
ID card
- Common name
- Large-flowered evening primrose
- Family
- Onagraceae
- Form
- Aquatic/semi-aquatic herb
- Flowering
- June to September, yellow flowers
- Foliage
- Deciduous or semi-evergreen depending on climate
- Growth
- Very fast and vigorous
- Hardiness
- Moderate, frost-sensitive (< -5°C)
- Origin
- South America (Brazil, Paraguay)
Care
Watering and aquatic environment
The large-flowered evening primrose thrives in moist to aquatic conditions: it roots in mud, banks, or shallow basins. Keep the substrate constantly moist or submerged depending on your desired depth. In a pot, water generously without letting it dry out between waterings.
Light exposure
Place the plant in sun or partial shade for optimal flowering. It tolerates partial shade but produces fewer flowers. Sunny exposure (6 to 8 hours) stimulates growth and flowering.
Substrate and growing medium
Use soil rich in organic matter, or specialized aquatic plant compost if growing in a basin. In a pot, a mix of potting soil and peat works well. The plant adapts to various soil types as long as moisture remains constant.
Nutritional support
Apply balanced fertilizer (moderate NPK) once a month during the growing season (April to September). In aquatic environments, reduce applications: nutrients typically come from the water and organic debris. Avoid overfeeding, which promotes algae growth.
Pruning and growth control
Prune regularly in late winter or spring to manage expansion: the large-flowered evening primrose grows very quickly and can become invasive. Remove dead stems and spent flowers. Cut back shoots to limit proliferation.
Pests and common issues
The plant is generally robust, but watch for algae buildup and water eutrophication. In pots, excess moisture can promote root rot. In cold climates, it won't survive outdoors in winter: bring it indoors or protect it before frost.
Did you know?
Native to South America, the large-flowered evening primrose has become a major invasive species in Europe, notably in France in the marshes and canals of the southwest. Its exceptionally rapid growth and dense root system suffocate local aquatic ecosystems. As an ornamental plant, it should be grown in controlled settings to prevent its natural spread into wild aquatic habitats.
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
- Pink evening primroseOenothera speciosa
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- Evening primroseOenothera fruticosa
- Bolivian fuchsiaFuchsia boliviana
- ClockweedOenothera lindheimeri
Tips generated and checked by Viridia — adapt them to your local climate.