Ludwigia microcarpa (smallfruit primrose-willow)

Plate 1 figs. a–h · 8 separate observations

Ludwigia microcarpa, photographed by Matt Berger — fig. a Matt Berger, CC BY 4.0 / 2021-08-23 / obs. 153791843

Ludwigia microcarpa, photographed by Eric Knight — fig. b Eric Knight, CC BY 4.0 / obs. 142486619

Ludwigia microcarpa, photographed by Ben Machado — fig. c Ben Machado, CC BY 4.0 / obs. 110467641

Ludwigia microcarpa, photographed by Jessica — fig. e Jessica, CC BY 4.0 / obs. 66756185

Ludwigia microcarpa, photographed by Brandon Corder — fig. f Brandon Corder, CC BY 4.0 / obs. 59803596

Ludwigia microcarpa, photographed by Stan Shebs — fig. g Stan Shebs, CC BY-SA 4.0 / obs. 167656512

Ludwigia microcarpa, photographed by natalie — fig. h natalie, CC0 1.0 / obs. 136811692

Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.

Native range 15 botanical countries

Native distribution of Ludwigia microcarpa, after Kew’s World Checklist of Vascular Plants. Introduced, extinct and doubtful records are excluded, so this is where the plant is from, not everywhere it now grows. Regions too small to draw at this scale are marked with a dot.

Region	TDWG code	Continent
Alabama	ALA	NORTHERN AMERICA
Arkansas	ARK
Florida	FLA
Georgia	GEO
Louisiana	LOU
Mississippi	MSI
Missouri	MSO
North Carolina	NCA
South Carolina	SCA
Tennessee	TEN
Texas	TEX
Virginia	VRG
Bahamas	BAH	SOUTHERN AMERICA
Cuba	CUB
Jamaica	JAM

Region boundaries approximated from Natural Earth (public domain) and mapped to TDWG World Geographical Scheme for Recording Plant Distributions (WGSRPD) level-3 botanical countries (Brummitt 2001). Indicative, not the official WGSRPD geometry.

Where it actually grows measured, from 470 observations

Condition	5th percentile	Median	95th percentile
Coldest month, mean daily low	-0.2 °C	13.9 °C	16.8 °C
Warmest month, mean daily high	30.0 °C	31.1 °C	32.7 °C
Annual rainfall	1,315 mm	1,461 mm	1,706 mm
Rainfall in the driest quarter	132 mm	186 mm	333 mm

It is found where winters bring light frost. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 470 research-grade observations of Ludwigia microcarpa that carry a coordinate, and this is the range those places actually span. The 5th and 95th percentiles are used rather than the minimum and maximum, because a single cultivated specimen in a heated conservatory should not widen a tropical plant's range to the Arctic.

This is not a hardiness zone. A USDA zone is the average annual extreme minimum temperature. The figure above is the mean daily minimum of the coldest month, which is a different quantity and is typically far warmer. Reading one as the other would place a plant several zones too warm, so we do not publish a hardiness zone, because we do not have one.

Also published as 2 synonyms

A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.

Isnardia microcarpa Poir.
Ludwigia glandulosa Pursh

Sourcesevery claim on this page

World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
Kew, World Checklist of Vascular Plants (WCVP v16). native distribution by TDWG level-3 botanical country, and life form. CC BY 3.0. Retrieved 2026-06-04.

We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite.