Six-Petal Water Primrose

Ludwigia grandiflora ssp. hexapetala

Juvenile Ludwigia leaves are spatulate in shape and star-shaped in arrangement.

Five yellow petals at tips of stems, with lance shaped green leaves with white midveins.

Plant Description

A floating and emergent perennial Aquatic herbaceous plant with alternating spoon-shaped leaves with rounded apices on floating stems and alternating lance-shaped leaves with acute apices on upright stems. Stems are pubescent. Solitary flowers at leaf axils with 5-6 yellow petals. A number of invasive Ludwigia species and subspecies are found in the Willamette and are difficult to differentiate visually. Images shown here may or may not be Ludwigia grandiflora ssp hexapetala.

Plant Details

Life Forms	Aquatic
Habitats	Aquatic Canals Disturbed sites Ditches Floating Lakes Little Habitats Marshes Ponds Riparian areas Rivers Streams Wetlands
Soil and Moisture Conditions	All soil types Dry to wet
Suggested Actions	Report to Oregon Invasives Hotline Use BMPs to control on private property
Shade Preference	Full sun
Mature Height	flowering stems can rise up to 3 feet above the water
Distribution	Found in the Rogue and Willamette Rivers and their tributaries.
Control	Prevention is the best strategy , followed by early detection and rapid response. Report infestations to OregonInvasivesHotline.org.
Reproduction and Spread	Often spread as an ornamental for Aquatic Gardens. Spreads by seeds and stem fragments with movement of water, waterfowl, and recreational equipment.
Introduced	Native to South America; primarily introduced through ornamental plant trade.
Look Alikes	other Ludwigia species
Impact	Clogs Waterways, degrades wildlife habitat, negatively impacts water quality and Aquatic recreation.
More Info	https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=2979 https://www.nwcb.wa.gov/weeds/water-primrose https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=2979