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An example collection, so you can see what this page does. Nothing added here is kept: leaving deletes it.
Pontederia azurea; photograph Vincent A. Vos, CC BY, iNaturalist via GBIF CC BYVincent A. Vos, CC BY, iNaturalist via GBIF

Pontederia azurea Sw.

Anchored water hyacinth; Saw-petal water-hyacinth

Pontederiaceae · Mexico Southwest, Mexico Southeast +24

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Pontederia azurea, photograph Gabriel Jovêncio Ribeiro, CC BY, iNaturalist via GBIFPontederia azurea, photograph Gabriel Jovêncio Ribeiro, CC BY, iNaturalist via GBIFPontederia azurea, photograph Pablo Bombín, CC BY, iNaturalist via GBIFPontederia azurea, photograph cactusauria, CC BY, iNaturalist via GBIFPontederia azurea, photograph cactusauria, CC BY, iNaturalist via GBIFPontederia azurea, photograph Luis Capeletti, CC0, iNaturalist via GBIF 24 photographs ›
Habitat figures
Cold floor (1 night in 100)
5.1°C
Record low -0.7 °C in 44 years, at a typical spot in the range NASA POWER
Warmest month, mean daily high
31°C
Jan at the habitat CHELSA
Rain a year (median across the range)
1,383mm
12 months of 25 mm or more in the median year CHELSA
Open-sky light
22–38DLI
Lowest to highest month (DLI) CHELSA
The year in your months, northern hemisphere
  1. Jan
  2. Feb
  3. Mar
  4. Apr
  5. May
  6. Jun
  7. Jul
  8. Aug
  9. Sep
  10. Oct
  11. Nov
  12. Dec
Wet summers: the rain comes April to October (October to April at the habitat), read as a summer growing season. rain rule, CHELSA
Northern hemisphere unless you set your site. The chart is in the habitat's months.

Summary

Pontederia azurea is a water hyacinth from the Americas, sometimes known as anchored water hyacinth. It is the type species of Pontederia subg. Eichhornia, which was previously recognized as part of the polyphyletic genus Eichhornia. It is of some interest as an aquarium plant.

Quoted from Wikipedia, "Pontederia azurea", CC BY-SA 4.0.

About the genus · Pontederia

Pontederia is a genus of tristylous aquatic plants, members of which are commonly known as pickerel weeds. Pontederia is endemic to the Americas, distributed from Canada to Argentina, where it is found in shallow water or on mud. The genus was named by Linnaeus in honour of the Italian botanist Giulio Pontedera.

Quoted from Wikipedia, "Pontederia", CC BY-SA 4.0.

Cultivation

Seasons

The rain rule reads a summer growing season: 70% of the median year's rain (963 mm of 1,315 mm) falls in October to April, warmer than the year (wet-season mean 25.2 °C against a yearly mean of 23.6 °C). Months are the habitat's, southern hemisphere; shifted six months for a northern-hemisphere collection: April to October.

Rain

1,315 mm in the median year at the habitat, 963 mm of it October to April. Wettest month January at 149 mm, driest month August at 53 mm. Across the grid cells of the range the year's total runs 1,116 mm to 2,421 mm, the 10th to 90th percentile of each cell's own year. The median of the cells' own yearly totals, 1,383 mm, is the year's rain at the top of the page; the 1,315 mm here is the median year's, the twelve monthly medians added, which the rain rule reads. Habitat calendar, southern hemisphere; median year across the grid cells of the range, CHELSA.

Light

Open sky over the habitat: 22 to 38 mol/m²/day across the year (daily light integral, median year across the grid cells of the range, CHELSA; the lowest 10th-percentile month across the cells is 15, the highest 90th-percentile month 46).

Warmth and air
Temperature

Coldest: the 1st-percentile night over 44 years at a typical spot in the range is 5.1 °C, the absolute minimum -0.7 °C, 4 frost nights in 44 years (NASA POWER daily minima). Warmest: the 99th-percentile day is 40.2 °C. Monthly means: the coldest month's mean nightly low 15.5 °C in July (across the grid cells of the range 7.7 °C to 23.7 °C), the warmest month's mean daily high 30.5 °C in January (median year across the grid cells of the range, CHELSA). Cold floor: 5.1 °C, which is the 1st-percentile night over 44 years at a typical spot in the range (NASA POWER).

Humidity

Relative humidity at the habitat: 59 to 63% across the year (monthly means, median year across the grid cells of the range, CHELSA). A figure about the air, saying nothing about how the plant takes water.

How this section is made

Each card states this species' habitat figures with their sources, and what two fixed rules read from them; nothing here says what the plant does, wants or tolerates. The rules · the terms.

Seasons. Read from the median year of CHELSA monthly rainfall and mean temperature across the grid cells of the range: 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 moves 4 °C or more and the habitat lies 10° or more from the equator. A reading of the curves, not an observation of the plant.

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

Light. 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.

Temperature. NASA POWER daily minima and maxima over 44 years at a typical spot in the range, lapse-corrected -58 m to its elevation; CHELSA monthly means, median year across the grid cells of the range. The cold floor is the 1st-percentile night named in its sentence. Not a measured survival limit for any plant in a pot.

Humidity. CHELSA relative humidity, median year across the grid cells of the range.

Climate across the habitat

Habitat months, southern hemisphere

Habitat climate of Pontederia azurea through the yearWarmest month January, mean daily high 31 °C; coldest month July, mean nightly low 15.5 °C; 1,315 mm of rain in the median year (the twelve monthly medians added). Medians across the range, from CHELSA; the extremes at the edge from NASA POWER. Habitat months, southern hemisphere.-10°0°10°20°30°40°50°frost40.2° 99th-percentile day, NASA POWER-0.7° lowest night in 44 years, NASA POWER°C · day and nightcold quarter0100200300400mm rainDLI 22–38RH 59–63%JanFebMarAprMayJunJulAugSepOctNovDec
day night rain medians and 10th–90th percentile across 499 habitat cells, CHELSA cold quarter: the three months around the coldest month's mean nightly low extremes over 44 years at a typical spot in the range, from NASA POWER, marked at the edge, in no month DLI, mol/m²/dayRH %each on its own scale
Figures by month
JanFebMarAprMayJunJulAugSepOctNovDec
Day °C31 / 27–3230 / 27–3129 / 26–3128 / 22–3126 / 19–3025 / 16–2924 / 15–3026 / 17–3127 / 19–3228 / 22–3328 / 24–3230 / 26–31
Night °C23 / 20–2422 / 19–2422 / 18–2420 / 14–2418 / 11–2416 / 9–2416 / 8–2417 / 9–2418 / 10–2420 / 13–2421 / 16–2422 / 18–24
Rain mm149 / 51–265142 / 58–237143 / 48–236116 / 71–25596 / 47–30169 / 21–28355 / 13–28053 / 21–26079 / 47–270123 / 86–271146 / 94–214144 / 74–221
DLI38 / 30–4637 / 31–4033 / 30–3627 / 23–3324 / 18–3022 / 15–3023 / 16–3228 / 22–3530 / 27–3636 / 30–3838 / 28–4337 / 29–46
RH %62 / 55–6762 / 57–6861 / 58–6862 / 59–6862 / 59–6963 / 58–6961 / 55–6859 / 53–6859 / 54–6859 / 57–6860 / 56–6861 / 56–68
How this section is made
Each figure is the median across the 499 grid cells on land that hold in-range records (796 records in those cells; 3 more cells hold records but no land by the elevation layer, so those records sit at sea and the cells are left out), with the 10th–90th percentile span across those cells after the slash where it differs. A dash is a month one or more of those cells has no figure for in the grid (a variable CHELSA does not carry there), so no median is taken rather than one over fewer cells. Extremes and elevation were read at a typical spot in the range, cell 2229:2457 (-21.475, -57.125). Over 44 years there: absolute minimum -0.7 °C, 1st-percentile night 5.1 °C, 99th-percentile day 40.2 °C. Normals: CHELSA V2.1 1981–2010 climatology, 0.05° cells (each the mean of ~36 1 km pixels). Across the range: median and 10th–90th percentile of each month across the 499 distinct grid cells holding 796 of the 799 in-range records (3 further cells with records at sea, by the elevation layer, left out); extremes and elevation at the typical cell 2229:2457 (its coldest month's mean nightly low nearest the median across cells); its position is the cell centre. Extremes: NASA POWER (MERRA-2) daily 1981–2024, cell -21.50_-56.875, lapse-corrected -58 m at 6.5 °C/km. Elevation: ETOPO 2022, 335 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 the cells of the in-range records placed well enough to read one, not at the marker.
Openly licensed records inside the range, framed on where they fall.
NativeMexico Southwest, Mexico Southeast, Costa Rica, Guatemala, Honduras, Nicaragua, Panama, Cuba, Dominican Republic, Trinidad-Tobago, French Guiana, Guyana, Surinam, Venezuela, Bolivia, Colombia, Ecuador, Peru, Brazil West-Central, Brazil Northeast, Brazil Southeast, Brazil North, Brazil South, Argentina Northeast, Paraguay, Uruguay · introduced: Bangladesh, Myanmar, Florida · regions are the level-3 units of the World Geographical Scheme for Recording Plant Distributions, as Kew's World Checklist records ranges, some under historical names such as Yugoslavia or Czechoslovakia (how).
Map marker-28.7, -57.75 · in the densest population, 403 records (30% of those in range)
Kew's description“hydroperennial” · “wet tropical” · quoted from WCVP, RBG Kew (CC BY 4.0); not derived here
Evidence usedThe map marker rests on all 1348 georeferenced records inside the native range; the climate across the range on the 796 of them in the land cells it reads, of 799 placed to within 10 km; the map shows only the 798 openly licensed ones, which alone would put the marker 1144 km away. 26 records outside the WCVP native range not used. 549 in-range records are placed to worse than 10 km, or with no stated accuracy (admitted only as a person's observation to three decimals), and stay on the map but off the climate.
How this section is made
The map marker: the openly licensed record nearest the middle of the densest 1° population inside the densest 4° block of the 1348 in-range records; it decides nothing. Records outside the native range, living specimens and records marked introduced are not used; which records count.

Photographs

Pontederia azurea, photograph 1did not loadPontederia azurea, photograph 2did not loadPontederia azurea, photograph 3did not loadPontederia azurea, photograph 4did not loadPontederia azurea, photograph 5did not loadPontederia azurea, photograph 6did not load

Photographs: Gabriel Jovêncio Ribeiro, CC BY, iNaturalist via GBIF (2); Pablo Bombín, CC BY, iNaturalist via GBIF; cactusauria, CC BY, iNaturalist via GBIF (2); Luis Capeletti, CC0, iNaturalist via GBIF.

Similar habitat climate The 6 nearest by mean daily high, mean nightly low and rain, month by month. How.

Pacourina edulis Pacourina edulis Asteraceae Photo: CC BY, Silvia TenPontederia crassipes Pontederia crassipes Floating water-hyacinth Photo: CC BY, Donald DavesnePontederia rotundifolia Pontederia rotundifolia Tropical pickerelweed Photo: CC BY, Silvia Ten Philodendron mello-barretoanum Araceae Aquarius macrophyllus Aquarius macrophyllus Alismataceae Photo: CC0, filipepratesSwartzia jorori Swartzia jorori Fabaceae Photo: CC BY, Raquel Mondino

Other Pontederia 12 in the reference

Pontederia cordata Pontederia cordata Pickerelweed Photo: CC BY, RAPPontederia crassipes Pontederia crassipes Floating water-hyacinth Photo: CC BY, Donald DavesnePontederia cyanea Pontederia cyanea Blue Hyacinth Photo: CC BY, Joachim BlatchlyPontederia diversifolia Pontederia diversifolia Variableleaf Water Hyacinth Photo: CC BY, Guillaume Delaitre Pontederia elata Pontederiaceae Pontederia hastata Pontederia hastata Asian Water Hyacinth Photo: CC BY-SA, Bruno viardotPontederia korsakowii Pontederia korsakowii Pontederiaceae Photo: CC BY, Kim, Hyun-taePontederia paniculata Pontederia paniculata Brazilian water hyacinth Photo: CC0, Taize Santos Pontederia plantaginea Pontederiaceae Pontederia rotundifolia Pontederia rotundifolia Tropical pickerelweed Photo: CC BY, Silvia TenPontederia sagittata Pontederia sagittata Pontederiaceae Photo: CC BY, Douglas Caro LopezPontederia vaginalis Pontederia vaginalis Oval-leaf monochoria Photo: CC BY, chiuluan

Names & registers

Also known as Eichhornia aquatica; Eichhornia azurea; Eichhornia azurea var. genuina; Eichhornia azurea var. rhizantha; Eichhornia azurea var. rigida and 5 more. (GBIF Backbone)

GBIFWikipedia

The record

Family
Pontederiaceae
Described by
Sw.
Native to
Mexico Southwest, Mexico Southeast, Costa Rica +23
Wild records
1348 in range · 798 open

Every figure here is derived from public data by a stated rule and names its source; nothing about this species is written for its page by a person or by AI, apart from the marked, credited quotations. How →

Where this page came from built 2026-10-22
GBIF species record gbif.species answeredasked 2026-10-22
GBIF synonyms gbif.synonyms answeredasked 2026-10-22
GBIF common names gbif.vernacular answeredasked 2026-10-22names fetched 2026-10-22
WCVP native range wcvp.distribution answeredas of 2026-06-04
GBIF occurrence records gbif.occurrences answeredas of 2026-10-21GBIF occurrence download https://doi.org/10.15468/dl.hbdw64, of 2026-10-21; 11 records within 1 km of a botanic garden, herbarium or zoo left out (9 at a botanic garden or arboretum, 1 at a herbarium, 1 at a zoo; Wikidata's list)
Habitat climate climate answeredasked 2026-10-22
Daily extremes (NASA POWER) climate.extremes answeredasked 2026-10-22NASA POWER (MERRA-2) daily 1981–2024, cell -21.50_-56.875, lapse-corrected -58 m at 6.5 °C/km
Wikidata wikidata not taken: two items answeredasked 2026-10-22not taken: two items answered to the older names' GBIF records (Q3009554, Q112157013)
Wikipedia wikipedia answeredasked 2026-10-22
iNaturalist taxon inat.taxon not asked
iNaturalist photographs, wild inat.photos.wild not asked
iNaturalist photographs, cultivated inat.photos.cultivated not asked
GBIF media gbif.media answeredasked 2026-10-22
OpenAlex papers openalex not askednot yet asked for this reference; a later fill takes the papers from OpenAlex's snapshot

Every source is recorded as having answered, reported nothing, refused, failed, not been asked, or answered twice where one answer is taken (“not taken: two items answered”), and, for a source asked when this page was built, when: the figures are as the source held them that day; a source read from a file (Kew's World Checklist, a GBIF download) says "as of" the file's day instead; a row carried from an earlier build of the page names that build instead. Only “nothing to report” is ever shown as an absence. Records came from 148 datasets via GBIF.org; each carries its own licence.

Cultifolio

Opening your plants…