Onagraceae
Uruguay Water-Primrose (Ludwigia grandiflora)
Ludwigia grandiflora
A bog and pond-edge plant: it needs full sun and roots that are always in water or wet mud. It grows very fast and regrows from any piece of stem. It cannot be grown in the EU or released in Britain; where it is allowed, keep it in a closed container and never put any bits into drains or waterways.
Every 2 days
Direct sun
° - °C
% - %
Categories
What is Uruguay water-primrose?
Uruguay water-primrose (Ludwigia grandiflora) is a easy-care plant from the Onagraceae family. Uruguay water-primrose (Ludwigia grandiflora) is an amphibious perennial in the willowherb family (Onagraceae), native to South America and parts of the USA. It grows in ponds, ditches, canals, slow rivers and wet meadows and copes with water levels going up and down. Its stems creep 4 to 5 m out fr...
Uruguay water-primrose grows up to 1.0m, spread of 500cm, watering every 2 days. It is not suitable for indoor environments and safe for pets.
Unlike many tropical plants, Uruguay water-primrose tolerates watering mistakes. Best for beginners. Unlike many popular species, Uruguay water-primrose is safe to keep around pets.
How to Care for Uruguay water-primrose?
TLDR: Uruguay water-primrose needs Direct sun, watering every 2 days, and temperatures between 15-30°C with 40-70% humidity.
How Often Should You Water Uruguay water-primrose?
Keep the roots underwater or in saturated mud at all times. In a pot, stand it in a tub of water and top up what evaporates.
How Much Light Does Uruguay water-primrose Need?
Full sun. In shade it flowers poorly.
What Is the Best Soil for Uruguay water-primrose?
It roots in the mud of pond margins. In a container use heavy clay soil topped with gravel so it does not float away.
What Pot Should You Use for Uruguay water-primrose?
A watertight tub with no drainage holes, so the plant cannot escape.
What Is Uruguay water-primrose and Where Does It Come From?
Uruguay water-primrose (Ludwigia grandiflora) is an amphibious perennial in the willowherb family (Onagraceae), native to South America and parts of the USA. It grows in ponds, ditches, canals, slow rivers and wet meadows and copes with water levels going up and down. Its stems creep 4 to 5 m out from the bank and rise up to 1 m above the water, with narrow willow-like leaves. From midsummer to early autumn it has large bright yellow flowers with 5 or 6 petals. Outside its native range it is a serious invader: it forms dense mats that cover the water, use up oxygen and crowd out native plants. Since 2016 it has been banned in the EU, including keeping it in a closed pond, and in Great Britain it is an offence to plant it or let it spread in the wild.
How to Propagate Uruguay water-primrose?
Stem cuttings
It roots so easily that any loose fragment can become a new plant. That is why it spreads: do not propagate it where it is banned and never throw cuttings into water.
- 1 Cut a piece of stem with a few nodes
- 2 Push it into wet mud or float it in water
- 3 Keep it in sun until roots grow from the nodes
Materials needed:
How Big Does Uruguay water-primrose Grow?
TLDR: Uruguay water-primrose can reach up to 1.0m tall with Fast growth rate.
Max height
1.0m
Spread
5.0m
Growth rate
Fast
Foliage
Deciduous
Plant Uses
Ornamental
Great for decoration
Is your plant showing symptoms?
Click on the symptom to discover possible causes:
What Diseases Commonly Affect Uruguay water-primrose?
TLDR: Uruguay water-primrose is susceptible to 1 known diseases. Monitor regularly for early detection.
Fun Facts
It was brought to France in the 19th century as an ornamental and has since spread to at least nine European countries
Its mats can stand so high above the water that a pond looks like dry land
A flea beetle of the genus Lysathia feeds on the leaves and can strip whole stands
Frequently asked questions
Can I grow water primrose in my pond?
Why is it invasive?
When does it flower?
What should I do if it turns up in my pond?
Compare with similar plants
| Attribute | Difficulty | Light | Watering | Pet Safe |
|---|---|---|---|---|
| Field Maple | Easy | Bright indirect | 14d | ✓ |
| Iberian Houseleek | Easy | Direct sun | 14d | ✓ |
| Silver Birch | Easy | Direct sun | 14d | ✓ |
| Common Blanketflower | Easy | Direct sun | 10d | ✓ |
Choose & Compare
Sources & References
- Invasive Species Northern Ireland - Water primrose (Ludwigia grandiflora)
- neobiota.lu (MNHN Luxembourg) - Ludwigia grandiflora
- GB Non-native Species Secretariat - Uruguay Water-primrose
- Arnside & Silverdale AONB - ID sheet Ludwigia grandiflora
- J. Aquatic Plant Management 34 - water primrose flea beetle (Lysathia ludoviciana)
