Species
+

Commelina erecta L.

Blousel Blommetjie, Blue Commelina, Coastal Blue Dayflower, Erect Dayflower

Climate known 59 photographs Tropical foliage plant
Add one to my plants Sow seed

Every figure on this page is derived from public data by a stated rule and says its source; nothing here is written by a person or a model, except the Wikipedia passage, which is quoted and marked as such. How it is made.

Summary

Commelina erecta, commonly known as white mouth dayflower, slender dayflower, or widow's tears. C. erecta is a blue flower often recognized by its two large blue petals and smaller white petal. It is a perennial herb common across the world and native throughout the Americas, Africa and western Asia.

Text from Wikipedia, “Commelina erecta”, CC BY-SA 4.0, quoted as written. Kept separate from everything derived here.

About the genus · Commelina

Commelina is a genus of approximately 208 species commonly called dayflowers due to the short lives of their flowers, and less often known as widow's tears. It is by far the largest genus of its family, Commelinaceae. The Swedish taxonomist Carl Linnaeus of the 18th century named the genus after the two Dutch botanists Jan Commelijn and his nephew Caspar, each representing one of the showy petals of Commelina communis.

Text from Wikipedia, “Commelina”, CC BY-SA 4.0, quoted as written.

Family
Commelinaceae
Described by
L.
Native to
Cape Verde, Benin, Burkina +120
Wild records
1925 in range· 728 open

At a glance

Warmest month
31°C
Jul, mean day; nights 23 °C (CHELSA)
Rain
958mm/yr
12 wet months · peak Jun 112 mm (CHELSA)
Light
22–40DLI
mol/m²/day, winter to summer, open sky (CHELSA shortwave)
In short condensed by rule from the cultivation cards · not written by a person
Grouped as a tropical foliage plant by Commelinaceae, which is usually but not always one kind of plant (archetype table). Rain rule: no season, 70% of the rain takes 8 months (March and May to November in the northern hemisphere). Habitat rain 958 mm a year, wettest June at 112 mm, driest January at 57 mm (habitat calendar, northern hemisphere). Open sky over the habitat: 22 to 40 mol/m²/day. Cold floor 12 °C (archetype minimum for a tropical foliage plant, above the 4.3 °C habitat night).
Each sentence is one card's own one-line form, written by the same rule as the card (Its year, Rain, Light, Temperature); the note cannot say what a card does not. Months are given for the northern hemisphere (set your site in Settings to change this), and the habitat's own alongside. The cards · the figures.

Also known as Commelina albescens C.B.Clarke; Commelina auriculata E.May.; Commelina bahiensis Hoffmanns.; Commelina bahiensis Hoffmanns. ex Spreng.; Commelina bahiensis Willd. and 11 more.

Cultivation

Grouped as a tropical foliage plant by Commelinaceae, which is usually but not always one kind of plant (archetype table). The table supplies one figure for this group, a conventional minimum for the cold floor, and no prose.

Its year Rain rule: no season, 70% of the rain takes 8 months (March and May to November in the northern hemisphere).

This species’ habitat figures, and what two fixed rules read from them.

The rain rule reads no season: 70% of the year's rain (705 mm of 958 mm) takes 8 months, March and May to November. Mean temperature moves 11.2 °C between the warmest and coldest month. Months are the habitat's, northern hemisphere; shifted six months for a southern-hemisphere collection: November to May and September.

Read from the median year of CHELSA monthly rainfall and mean temperature across the envelope cells: the rain rule takes the smallest set of months carrying 70% of the rain and calls it winter when its mean is more than half a degree below the year's, summer when more than that above, and neither in between; the temperature rule, used only under 120 mm, names the cooler six months when they are at least a degree cooler than the other six. Months are shifted for the other hemisphere only where the temperature curve gives a season to reverse. A reading of the curves, not an observation of the plant.

Rain Habitat rain 958 mm a year, wettest June at 112 mm, driest January at 57 mm (habitat calendar, northern hemisphere).

This species’ habitat figures, with their source.

958 mm a year at the habitat, 705 mm of it March and May to November. Wettest month June at 112 mm, driest January at 57 mm. Across the envelope cells the year's total runs 572 mm to 1633 mm (10th to 90th percentile of each cell's own year) (median year across the envelope cells, CHELSA; habitat calendar, northern hemisphere).

CHELSA monthly precipitation, median year across the envelope cells. The rain that falls where the species is recorded; nothing about how the plant takes water.

Light Open sky over the habitat: 22 to 40 mol/m²/day.

This species’ habitat figures, with their source.

Open sky over the habitat: 22 to 40 mol/m²/day across the year (daily light integral, median year across the envelope cells, CHELSA; the lowest 10th-percentile month across the cells is 16, the highest 90th-percentile month 44).

CHELSA shortwave radiation at each envelope cell, a daily-mean flux taken to a daily total and converted at 2.07 mol of PAR per MJ. The sky over the habitat, measured; what reaches a plant under a rock, a shrub or a shade cloth is not.

Warmth and air Cold floor 12 °C (archetype minimum for a tropical foliage plant, above the 4.3 °C habitat night).

This species’ habitat figures, with their source.

Temperature

Coldest: the 1st-percentile night over 44 years at the typical cell is 4.3 °C, the absolute minimum 0.0 °C, no frost in 44 years (NASA POWER daily minima). Warmest: the 99th-percentile day is 40.5 °C. Monthly means: coldest night 11.8 °C in January (across the envelope cells 1.8 °C to 23.1 °C), warmest day 30.6 °C in July (median year across the envelope cells, CHELSA). Cold floor: 12 °C. The habitat figure, the 1st-percentile night over 44 years at the typical cell (NASA POWER), is 4.3 °C; the archetype table's conventional minimum for a tropical foliage plant (grouped by Commelinaceae, which is usually but not always one kind of plant) is 12 °C, which is higher, and the floor rule takes the higher.

NASA POWER daily minima and maxima 1981–2024 at the typical cell, lapse-corrected to its elevation; CHELSA monthly means, median year across the envelope cells, CHELSA. The cold floor is the figure named in its sentence, and the archetype table's group minimum where that is higher. Not a measured survival limit for any plant in a pot.

Humidity

Relative humidity at the habitat: 58 to 61% across the year (monthly means, median year across the envelope cells, CHELSA). A figure about the air, saying nothing about how the plant takes water.

CHELSA relative humidity, median year across the envelope cells.

The figures the cards read from are in Climate below, and where they came from in Natural habitat.

Climate across the habitat

Habitat climate through the yearMean day from 21 °C in Jan to 31 °C in Jul; mean night from 12 °C in Jan to 23 °C in Jul. The cold quarter, Dec to Feb, is the three months around the coldest night. 958 mm of rain a year, most in Jun. The bands show the 10th to 90th percentile across 1549 habitat cells. Over 44 years at the typical cell the absolute minimum was 0.0 °C and the 99th-percentile day 40.5 °C; neither is dated to a month. Beneath: daily light integral and relative humidity through the year, each on its own scale.-10°10°20°30°40°50°frost40.5° 99th-percentile day (undated)0.0° lowest night in 44 yrs (undated)°C · day and nightcold quarter050100150200250mm rainDLI 22–40RH 58–61 %JanFebMarAprMayJunJulAugSepOctNovDec
day night rain 10th–90th percentile across 1549 habitat cells cold quarter: the three months around the coldest night extremes over 44 years at the typical cell, marked at the edge: undated DLI, mol/m²/dayRH %each on its own scale
Figures by month
JanFebMarAprMayJunJulAugSepOctNovDec
Day °C21 / 13–3123 / 15–3124 / 19–3126 / 22–3129 / 22–3230 / 21–3331 / 21–3431 / 23–3529 / 24–3227 / 22–3024 / 18–3022 / 13–30
Night °C12 / 2–2313 / 3–2315 / 7–2416 / 11–2419 / 12–2422 / 12–2523 / 12–2523 / 13–2521 / 13–2517 / 12–2415 / 7–2313 / 3–23
Rain mm57 / 14–14263 / 13–13876 / 15–14770 / 21–12595 / 24–153112 / 22–22780 / 28–20974 / 30–22492 / 40–232104 / 38–16972 / 18–15063 / 15–154
DLI24 / 18–4129 / 22–4033 / 28–4136 / 28–4438 / 24–4439 / 22–4340 / 23–4437 / 26–4133 / 29–3829 / 25–3725 / 19–4122 / 16–41
RH %58 / 53–6458 / 52–6458 / 52–6458 / 51–6560 / 53–6661 / 54–6760 / 53–6759 / 52–6759 / 53–6758 / 54–6658 / 53–6558 / 53–65

Each figure is the median across the 1549 grid cells holding the 1832 in-range records, with the 10th–90th percentile span across those cells after the slash where it differs. Extremes and elevation were read at the typical cell 1259:1352 (27.025, -112.375). Over 44 years there: absolute minimum 0.0 °C, 1st-percentile night 4.3 °C, 99th-percentile day 40.5 °C. Normals: CHELSA V2.1 1981–2010 climatology, 0.05° cells (each the mean of ~36 1 km pixels). Envelope: median and 10th–90th percentile of each month across the 1549 distinct grid cells holding the 1832 in-range records; extremes and elevation at the typical cell 1259:1352 (its coldest month's mean night nearest the median across cells); its position is the cell centre. Extremes: NASA POWER (MERRA-2) daily 1981–2024, cell 27.00_-112.500, lapse-corrected +133 m at 6.5 °C/km. Elevation: ETOPO 2022, 616 m (cell mean).

Natural habitat

Native range as published by WCVP; the marker is where the records are densest and decides nothing: the climate was read across every in-range record's cell, not at the marker.
Openly licensed records inside the range, framed on where they fall.
NativeCape Verde, Benin, Burkina, Gambia, The, Ghana, Guinea-Bissau, Guinea, Ivory Coast, Liberia, Mali, Nigeria, Niger, Senegal, Sierra Leone, Togo, Burundi, Central African Republic, Cameroon, Congo, Gulf of Guinea Is., Rwanda, Zaïre, Chad, Ethiopia, Somalia, Sudan, Kenya, Tanzania, Uganda, Angola, Malawi, Mozambique, Zimbabwe, Botswana, Cape Provinces, Namibia, KwaZulu-Natal, Free State, Swaziland, Northern Provinces, Saudi Arabia, Yemen, Colorado, Wyoming, Illinois, Iowa, Kansas, Minnesota, Missouri, Nebraska, Oklahoma, South Dakota, Wisconsin, Indiana, Michigan, New Jersey, New York, Pennsylvania, Rhode I., West Virginia, Arizona, New Mexico, Texas, Alabama, Arkansas, Delaware, Florida, Georgia, Kentucky, Louisiana, Maryland, Mississippi, North Carolina, South Carolina, Tennessee, Virginia, District of Columbia, Mexico Central, Mexico Northeast, Mexico Gulf, Mexico Northwest, Mexico Southwest, Mexico Southeast, Belize, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, Panama, Aruba, Bahamas, Bermuda, Cayman Is., Cuba, Dominican Republic, Haiti, Jamaica, Leeward Is. AB Ant, Netherlands Antilles, Puerto Rico, Southwest Caribbean, Turks-Caicos Is., Trinidad-Tobago, Venezuelan Antilles, Windward Is., French Guiana, Guyana, Surinam, Venezuela, Bolivia, Colombia, Ecuador, Peru, Brazil West-Central, Brazil Northeast, Brazil Southeast, Brazil North, Brazil South, Argentina Northeast, Argentina Northwest, Paraguay, Uruguay· introduced: Spain, Madeira, Palestine, Japan, Bangladesh, Chile Central
Kew's description“perennial or tuberous geophyte” · “seasonally dry tropical”· quoted from WCVP, RBG Kew (CC BY 4.0); not derived here
Map marker30.245, -97.852 · in the densest population, 320 records (17% of those in range)
Evidence usedThe map marker and the climate envelope rest on all 1925 georeferenced records inside the native range; the map shows only the 728 openly licensed ones, which alone would put the marker 93 km away. 11 records outside the range (gardens, roadsides, misidentifications) ignored. 93 in-range records are placed to worse than 10 km and stay on the map but off the climate.
The map markerthe map marker: the openly licensed record nearest the middle of the densest 1° population of the 1925 in-range records; it decides nothing.

Photographs

Commelina erectaCommelina erectaCommelina erectaCommelina erectaCommelina erectaCommelina erectaCommelina erectaCommelina erecta

Photographs: (c) Catherine C. Galley, some rights reserved (CC BY) (2); no rights reserved · CC0 (3); (c) Linda Jo Conn, some rights reserved (CC BY); (c) Nicolas Olejnik, some rights reserved (CC BY) (2).

Photographs: iNaturalist and Wikimedia Commons did not answer when this page was built; what is shown came from the sources that did.

Papers naming this species

Works whose title or abstract names Commelina erecta, most cited first, from OpenAlex (CC0). A mention, not a cultivation source: nothing on this page is drawn from them.

Stomatal cell wall composition: distinctive structural patterns associated with different phylogenetic groups
Ilana Shtein, Yaniv Shelef, Ziv Marom, Einat Zelinger (2017) · Annals of Botany
Physical barriers and corridors in urban habitats affect colonisation and parasitism rates of a specialist leaf miner
Guadalupe Peralta, María Silvina Fenoglio, Adriana Salvo (2011) · Ecological Entomology
Plant patch structure modifies parasitoid assemblage richness of a specialist herbivore
María Silvina Fenoglio, Adriana Salvo, Martín Videla, Graciela Valladares (2010) · Ecological Entomology
Anti-Staphylococcus aureus activity of methanol extracts of 12 plants used in Cameroonian folk medicine
Leonard Sama Fonkeng, Raymond Simplice Mouokeu, Tume Christopher, Guy Sedar Singor Njateng (2015) · BMC Research Notes
Liriomyza commelinae(Diptera: Agromyzidae): an alternative host for parasitoids of the leafminer pestLiriomyza huidobrensis
María Silvina Fenoglio, Adriana Salvo (2009) · International Journal of Pest Management
Glyphosate-induced structural variations in Commelina erecta L. (Commelinaceae)
Elisa S. Panigo, Ignacio Dellaferrera, Juan M. Acosta, Adrián G. Bender (2011) · Ecotoxicology and Environmental Safety
Chromosomes of four species of Commelina (Commelinaceae)
Mauro Grabiele, Julio R. Daviña, Ana I. Honfi (2005) · Botanical Journal of the Linnean Society
Identification of caffeic acid and rutin by UHPLC MS/MS and antioxidant activity of Commelina erecta Lineu. in cell culture
Felipe Akihiro Melo Otsuka, RODRIGO B. SANTOS, Larissa Oliveira Chaves, Rosangela S. Santos (2020) · Anais da Academia Brasileira de Ciências
Chemical Composition and Biological Activity of Commelina erecta: An Edible Wild Plant Consumed in Brazil
Lucas Vinicius Cavichi, Ângela Liberal, María Inês Días, Filipa Mandim (2023) · Foods

Similar habitat climate the 6 species whose habitat climate is nearest this one's: mean day and night, month by month, and rain on a log scale, in calendar order, so a habitat with the same seasons six months out is far, not near. Nothing else counts: not range, not family.

Other Commelina 1 in the reference

History & registers

Where this page came from built 2026-09-20 · dossier v2 · node
gbif.species answeredcarried from build of 2026-09-20 (offline re-derivation; the backbone was not asked)
gbif.synonyms answeredcarried from build of 2026-09-20 (offline re-derivation; the backbone was not asked)
gbif.vernacular answeredcarried from build of 2026-09-20 (offline re-derivation; the backbone was not asked)
wcvp.distribution answered
gbif.occurrences answeredGBIF occurrence download https://doi.org/10.15468/dl.3h4zam
climate answered
wikidata answeredcarried from build of 2026-09-20 (rederive); that build: carried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)
wikipedia answeredcarried from build of 2026-09-20; this build: skipped
inat.taxon not askedcarried from build of 2026-09-20 (rederive)
inat.photos.wild answeredcarried from build of 2026-09-20; this build: skipped
inat.photos.cultivated nothing to reportcarried from build of 2026-09-20 (rederive); that build: carried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)
commons not askedcarried from build of 2026-09-20 (rederive); that build: carried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)
gbif.media answered
openalex answeredcarried from build of 2026-09-20; this build: skipped

Every upstream is recorded as having answered, reported nothing, or refused. Only “nothing to report” is ever shown as an absence. Records came from 195 datasets via GBIF.org; each carries its own licence.