North America Non-native Plant

Floating Primrose-willow

Botanical name: Ludwigia peploides montevidensis

USDA symbol: LUPEM

Life cycle: perennial

Habit: forb

Native status: Non-native, reproduces and persists in the wild in the lower 48 states  

Synonyms: Jussiaea repens L. var. montevidensis (Spreng.) Munz (JUREM2)  âš˜  Ludwigia peploides (Kunth) P.H. Raven var. montevidensis (Spreng.) Shinners (LUPEM2)   

Floating Primrose-Willow: A Water-Loving Perennial for Aquatic Gardens If you’re looking to add some greenery to your water garden or pond margins, you might have come across floating primrose-willow (Ludwigia peploides montevidensis). This interesting aquatic perennial brings a unique charm to wet spaces, but there are some important things every ...

Floating Primrose-Willow: A Water-Loving Perennial for Aquatic Gardens

If you’re looking to add some greenery to your water garden or pond margins, you might have come across floating primrose-willow (Ludwigia peploides montevidensis). This interesting aquatic perennial brings a unique charm to wet spaces, but there are some important things every gardener should know before adding it to their landscape.

What is Floating Primrose-Willow?

Floating primrose-willow is a non-native perennial forb that’s made itself at home in parts of the United States. As a forb, it’s essentially an herbaceous plant without significant woody tissue – think of it as the aquatic cousin of your garden’s non-woody flowering plants. This plant has quite the family tree, with scientific synonyms including Jussiaea repens var. montevidensis and Ludwigia peploides var. montevidensis, showing how botanists have reclassified it over the years.

Where Does It Grow?

Originally hailing from South America, particularly the Uruguay and Argentina region, floating primrose-willow has established populations in California and Louisiana. It’s one of those introduced species that has found favorable conditions in certain parts of the lower 48 states and reproduces on its own without human assistance.

Garden Appeal and Characteristics

This aquatic beauty offers several appealing features for water gardeners:

  • Charming small yellow flowers that add color to water features
  • Mat-forming growth habit that can provide coverage over pond surfaces
  • Prostrate to floating stems that create interesting texture
  • Perennial nature means it returns year after year in suitable climates

Growing Conditions and Care

Floating primrose-willow is quite specific about its growing requirements, thriving in USDA hardiness zones 8-11. Here’s what it needs to flourish:

  • Moisture: Consistently wet to saturated soils or shallow water
  • Light: Full sun to partial shade
  • Habitat: Pond margins, bog gardens, or naturalized wetland areas
  • Maintenance: Minimal care once established, though monitoring spread is wise

This plant can spread vegetatively, creating larger colonies over time. While this makes it relatively low-maintenance, it’s something to keep in mind when planning your water garden layout.

Should You Plant It?

The decision to grow floating primrose-willow depends on your specific gardening goals and local conditions. While it’s not currently listed as invasive or noxious, being a non-native species means it’s worth considering some alternatives first.

Consider this plant if you:

  • Live in zones 8-11 and have appropriate wet conditions
  • Want low-maintenance aquatic coverage
  • Enjoy unique water garden specimens
  • Have space where spreading won’t be problematic

Native Alternatives to Consider

Before settling on floating primrose-willow, consider these native aquatic alternatives that might better support local ecosystems:

  • Native Ludwigia species appropriate to your region
  • Local water lilies or pond lilies
  • Regional sedges and rushes
  • Indigenous aquatic wildflowers

Check with your local native plant society or extension office for the best native aquatic options in your specific area.

The Bottom Line

Floating primrose-willow can be an attractive addition to the right water garden, offering easy care and interesting aquatic coverage. However, as a non-native species, it’s worth exploring native alternatives first. If you do choose to grow it, monitor its spread and ensure it doesn’t escape into natural waterways. Remember, the best garden choices are often those that work harmoniously with your local ecosystem while meeting your aesthetic goals.

Whatever you decide, happy water gardening!

Floating Primrose-willow

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Rosidae

Order

Myrtales

Family

Onagraceae Juss. - Evening Primrose family

Genus

Ludwigia L. - primrose-willow

Species

Ludwigia peploides (Kunth) P.H. Raven - floating primrose-willow

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA