64 photographs › At a glance
- Jan
- Feb
- Mar
- Apr
- May
- Jun, shaded
- Jul, shaded
- Aug, shaded
- Sep, shaded
- Oct, shaded
- Nov, shaded
- Dec
Summary
Ruellia prostrata is a species of flowering plant in the family Acanthaceae.
Quoted from Wikipedia, "Ruellia prostrata", CC BY-SA 4.0.
About the genus · Ruellia
Ruellia is a genus of flowering plants commonly known as ruellias or wild petunias. They are not closely related to petunias (Petunia) although both genera belong to the same euasterid clade. The genus was named in honor of Jean Ruelle (1474–1537), herbalist and physician to Francis I of France and translator of several works of Dioscorides.
Quoted from Wikipedia, "Ruellia", CC BY-SA 4.0.
Cultivation
Grouped as a tropical foliage plant, listed under the genus Ruellia in the archetype table, and Kew describes it as “annual or subshrub”, “seasonally dry tropical”.
Seasons
The rain rule reads a rainy season with no name: 70% of the median year's rain (926 mm of 1,185 mm) falls in June to November, whose mean temperature, 27.1 °C, is within half a degree of the year's, 26.8 °C, so it is neither the cooler nor the warmer part of the year. Months are the habitat's, northern hemisphere. The habitat lies within 10° of the equator, where the shift rule does not apply, so they are not shifted for a collection elsewhere.
Rain
1,185 mm in the median year at the habitat, 926 mm of it June to November. Wettest month October at 180 mm, driest month January at 17 mm. Across the grid cells of the range the year's total runs 834 mm to 2,467 mm, the 10th to 90th percentile of each cell's own year. The median of the cells' own yearly totals, 1,318 mm, is the year's rain at the top of the page; the 1,185 mm here is the median year's, the twelve monthly medians added, which the rain rule reads. Habitat calendar, northern hemisphere; median year across the grid cells of the range, CHELSA.
Light
Open sky over the habitat: 30 to 41 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 24, the highest 90th-percentile month 47).
Warmth and air
Coldest: the 1st-percentile night over 44 years at a typical spot in the range is 14.7 °C, the absolute minimum 11.1 °C, no frost in 44 years (NASA POWER daily minima). Warmest: the 99th-percentile day is 34.7 °C. Monthly means: the coldest month's mean nightly low 19.3 °C in January (across the grid cells of the range 11.9 °C to 24.1 °C), the warmest month's mean daily high 33.7 °C in April (median year across the grid cells of the range, CHELSA). Cold floor: 14.7 °C, which is the 1st-percentile night over 44 years at a typical spot in the range (NASA POWER).
Relative humidity at the habitat: 58 to 64% 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 -75 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.
Group. Listed under the genus Ruellia in the archetype table, and Kew describes it as “annual or subshrub”, “seasonally dry tropical”. A group is taken only where Kew's description of the species agrees with the table's listing. The table gives no figure and no prose; the cold floor is the habitat's alone.
Climate across the habitat
Habitat months, northern hemisphere
Mean daily high from 28 °C in Jan, Nov and Dec to 34 °C in Apr and May; mean nightly low from 19 °C in Jan to 26 °C in May and Jun. The cold quarter, Dec to Feb, is the three months around the coldest month's mean nightly low. 1,185 mm of rain in the median year (the twelve monthly medians added), the wettest month Oct. The bands show the 10th to 90th percentile across 294 habitat cells. Over 44 years at a typical spot in the range (NASA POWER) the absolute minimum was 11.1 °C and the 99th-percentile day 34.7 °C; neither is dated to a month. Beneath: daily light integral and relative humidity through the year, each on its own scale.
Figures by month
| Figure | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Day °C | 28 / 24–30 | 30 / 27–32 | 32 / 29–35 | 34 / 29–38 | 34 / 29–39 | 32 / 28–37 | 30 / 27–34 | 29 / 27–33 | 30 / 28–33 | 30 / 28–32 | 28 / 27–31 | 28 / 25–29 |
| Night °C | 19 / 12–24 | 20 / 14–25 | 22 / 18–25 | 25 / 21–26 | 26 / 22–27 | 26 / 22–28 | 25 / 22–26 | 25 / 21–26 | 24 / 21–26 | 23 / 19–25 | 21 / 16–25 | 20 / 13–24 |
| Rain mm | 17 / 3–143 | 21 / 2–90 | 32 / 4–119 | 64 / 4–222 | 85 / 10–262 | 124 / 33–292 | 161 / 43–406 | 164 / 37–351 | 175 / 68–298 | 180 / 27–315 | 122 / 9–308 | 40 / 3–216 |
| DLI | 32 / 29–37 | 38 / 34–40 | 41 / 39–43 | 41 / 36–47 | 39 / 32–47 | 34 / 29–38 | 31 / 25–36 | 31 / 24–37 | 33 / 29–38 | 32 / 30–36 | 30 / 27–32 | 30 / 26–34 |
| RH % | 59 / 49–66 | 58 / 45–64 | 58 / 42–64 | 60 / 41–66 | 61 / 45–67 | 62 / 53–69 | 63 / 57–70 | 64 / 57–69 | 63 / 58–68 | 63 / 51–67 | 63 / 47–67 | 60 / 49–67 |
Records on both sides of the equator: the 71 cells at least 10° south of it have seasons six months apart and are left out, not combined into a year no place has. These figures are across the 294 cells that remain: the 178 at least 10° north and the 116 within 10° of the equator, which stay in either way.
How this section is made
Natural habitat
How this section is made
Photographs
Photographs: (c) Andrew Parker, some rights reserved (CC BY); (c) Richard Littauer, some rights reserved (CC BY); (c) Ravuri Krishna Chaitanya, some rights reserved (CC BY); author not stated, no rights reserved · CC0; (c) Dave Shenton, some rights reserved (CC BY); (c) linkie, some rights reserved (CC BY).
Related
Similar habitat climate The 6 nearest by mean daily high, mean nightly low and rain, month by month. How.
Lagerstroemia tomentosa Lythraceae Photo: CC BY, Board of Trustees, RBG Kew
Calotropis gigantea Giant milkweed Photo: CC0, author not stated
Ouret lanata Aerva Photo: CC BY, white_cheeked_barbet
Borassus flabellifer Toddy palm Photo: CC BY-SA, Dinesh Valke
Nymphaea pubescens Hairy water lily Photo: CC BY, rajesh rocky
Basella alba Ceylon spinach Photo: CC0, author not statedOther Ruellia 37 in the reference
Ruellia affinis Acanthaceae Photo: CC BY, B. Phalan
Ruellia angustiflora Acanthaceae Photo: CC BY, William Stephens Ruellia angustifolia Acanthaceae 
Ruellia blechum Browne's blechum Photo: CC BY, Guillaume Delaitre Ruellia blumei Acanthaceae 
Ruellia bourgaei Acanthaceae Photo: CC0, author not stated
Ruellia breedlovei Acanthaceae Photo: CC BY, Neptalí Ramírez Marcial
Ruellia brevifolia Tropical wild petunia Photo: CC BY, Zoe Anthony Quested
Ruellia californica Acanthaceae Photo: CC BY, Drepanostoma
Ruellia caroliniensis Carolina wild petunia Photo: CC BY, portulaca
Ruellia chartacea Peruvian wild petunia Photo: CC BY, Yuri Sofronov
Ruellia ciliatiflora Hairyflower wild petunia Photo: CC BY, Reanne ("Bean") Dunn all 38 ›Names & registers
Also known as Dipteracanthus dejectus; Dipteracanthus flaviflorus; Dipteracanthus genduanus; Dipteracanthus prostratus; Dipteracanthus richardianus and 10 more. (GBIF Backbone)
Under another author Ruellia repens Wall. is an older name of this species, not Ruellia repens, a species of the reference. (GBIF Backbone)
The record
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 answeredasked 2026-10-22gbif.synonyms answeredasked 2026-10-22gbif.vernacular answeredasked 2026-10-22names fetched 2026-10-22wcvp.distribution answeredas of 2026-06-04gbif.occurrences answeredas of 2026-10-21GBIF occurrence download https://doi.org/10.15468/dl.hbdw64, of 2026-10-21; 54 records within 1 km of a botanic garden, herbarium or zoo left out (35 at a botanic garden or arboretum, 5 at a herbarium, 14 at a zoo; Wikidata's list)climate answeredasked 2026-10-22climate.extremes answeredasked 2026-10-22NASA POWER (MERRA-2) daily 1981–2024, cell 7.00_80.625, lapse-corrected -75 m at 6.5 °C/kmwikidata answeredasked 2026-10-22wikipedia answeredasked 2026-10-22inat.photos.wild answeredasked 2026-10-22from iNaturalist's open data of 2026-09-27: research-grade observations with an open-licence photograph, the 24 whose photographs iNaturalist received last (the open data holds no votes); filled 2026-10-22inat.photos.cultivated not askedgbif.media answeredasked 2026-10-22openalex not askednot yet asked for this reference; a later fill takes the papers from OpenAlex's snapshotEvery 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 52 datasets via GBIF.org; each carries its own licence.