Thunbergia alata Bojer ex Sims
Black Eyed Susan, Black eyed Susan vine, Black-eyed Susan, Black-eyed Susan clock vine, Bright eyes, Winged clockvine, Black-eyed Susan, Black-eyed Susan vine
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
Thunbergia alata, commonly called black-eyed Susan vine, is a herbaceous perennial climbing plant species in the family Acanthaceae. It is native to Eastern Africa, and has been naturalized in other parts of the world.
Text from Wikipedia, “Thunbergia alata”, CC BY-SA 4.0, quoted as written. Kept separate from everything derived here.
About the genus · Thunbergia
Thunbergia is a genus of flowering plants in the family Acanthaceae. It includes 150 species native to tropical and subtropical regions of sub-Saharan Africa, Madagascar, southern Asia, New Guinea, and Australia. Thunbergia species are vigorous annual or perennial vines and shrubs growing to 2–8 m tall. More on Wikipedia ›
The opening of Wikipedia, “Thunbergia”, CC BY-SA 4.0, quoted as written.
At a glance
Also known as Endomelas alata (Bojer ex Sims) Raf.; Thunbergia alata Bojer; Thunbergia alata var. alba Paxton; Thunbergia alata var. albiflora Hook.; Thunbergia alata var. minor S.Moore and 20 more.
Cultivation
Its year Rain rule: a summer growing season, October to April at the habitat (not shifted).
This species’ habitat figures, and what two fixed rules read from them.
The rain rule reads a summer growing season: 70% of the year's rain (850 mm of 1084 mm) falls in October to April, warmer than the year (wet-season mean 20.5 °C against a yearly mean of 19.4 °C). Months are the habitat's, southern hemisphere, within 10° of the equator; with no thermal season there there is no season to reverse, so they are not shifted for a collection elsewhere.
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 1084 mm a year, wettest April at 147 mm, driest June at 27 mm (habitat calendar, southern hemisphere).
This species’ habitat figures, with their source.
1084 mm a year at the habitat, 850 mm of it October to April. Wettest month April at 147 mm, driest June at 27 mm. Across the envelope cells the year's total runs 798 mm to 1864 mm (10th to 90th percentile of each cell's own year) (median year across the envelope cells, CHELSA; habitat calendar, southern 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: 28 to 37 mol/m²/day.
This species’ habitat figures, with their source.
Open sky over the habitat: 28 to 37 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 20, the highest 90th-percentile month 43).
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 9.0 °C (1st-percentile habitat night, NASA POWER).
This species’ habitat figures, with their source.
Coldest: the 1st-percentile night over 44 years at the typical cell is 9.0 °C, the absolute minimum 5.1 °C, no frost in 44 years (NASA POWER daily minima). Warmest: the 99th-percentile day is 29.1 °C. Monthly means: coldest night 11.9 °C in July (across the envelope cells 6.5 °C to 18.5 °C), warmest day 26.1 °C in February (median year across the envelope cells, CHELSA). Cold floor: 9.0 °C, which is the 1st-percentile night over 44 years at the typical cell (NASA POWER).
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. Not a measured survival limit for any plant in a pot.
Relative humidity at the habitat: 58 to 64% 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
Figures by month
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Day °C | 25 / 22–30 | 26 / 23–31 | 26 / 23–30 | 24 / 21–28 | 23 / 19–28 | 22 / 18–27 | 21 / 17–26 | 22 / 19–27 | 24 / 20–27 | 24 / 21–28 | 24 / 22–28 | 25 / 22–29 |
| Night °C | 16 / 12–22 | 17 / 12–22 | 16 / 13–22 | 16 / 12–21 | 14 / 10–20 | 13 / 7–19 | 12 / 7–19 | 13 / 8–19 | 14 / 9–19 | 15 / 11–20 | 15 / 12–21 | 16 / 12–21 |
| Rain mm | 124 / 35–278 | 111 / 40–246 | 122 / 88–224 | 147 / 48–270 | 91 / 17–212 | 27 / 8–130 | 29 / 3–139 | 34 / 6–151 | 53 / 13–165 | 96 / 38–214 | 124 / 87–182 | 126 / 65–237 |
| DLI | 37 / 33–41 | 37 / 34–43 | 35 / 31–41 | 32 / 27–36 | 30 / 23–35 | 28 / 20–34 | 28 / 21–34 | 31 / 25–36 | 36 / 29–41 | 37 / 31–42 | 36 / 31–42 | 37 / 32–40 |
| RH % | 63 / 56–68 | 62 / 55–67 | 63 / 56–68 | 64 / 59–70 | 62 / 56–70 | 59 / 53–67 | 58 / 50–67 | 59 / 51–66 | 60 / 50–65 | 61 / 52–66 | 63 / 56–67 | 63 / 58–68 |
Each figure is the median across the 159 grid cells holding the 207 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 1972:4312 (-8.625, 35.625). Over 44 years there: absolute minimum 5.1 °C, 1st-percentile night 9.0 °C, 99th-percentile day 29.1 °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 159 distinct grid cells holding the 207 in-range records; extremes and elevation at the typical cell 1972:4312 (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 -8.50_35.625, lapse-corrected -263 m at 6.5 °C/km. Elevation: ETOPO 2022, 1260 m (cell mean).
Natural habitat
Photographs
Photographs: (c) Viktor, some rights reserved (CC BY); (c) ldgc, some rights reserved (CC BY-SA) (2); (c) 呂一起(Lyu yi-chi), some rights reserved (CC BY) (5).
Photographs: iNaturalist 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 Thunbergia alata, most cited first, from OpenAlex (CC0). A mention, not a cultivation source: nothing on this page is drawn from them.
Related
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.
Senna didymobotrya African Wild Cassia
Momordica foetida Cucurbitaceae
Pentas lanceolata Egyptian Starcluster
Syzygium cordatum Umdoni Waterberry
Ekebergia capensis Cape-ash
Ceropegia semota ApocynaceaeOther Thunbergia 5 in the reference
Thunbergia erecta Bush Clockvine
Thunbergia grandiflora Bengal clock vine, Bengal trumpet, Blue sky vine, Blue trumpet vine, Clockvine, Bengal trumpet vine, Blue skyflower, Blue thunbergia, Skyflower, Skyvine, Heavenly blue, Giant thunbergia, Green trumpet vine, Large flowered thunbergia
Thunbergia gregorii Golden Clockvine
Thunbergia laurifolia Blue Trumpet Vine
Thunbergia mysorensis Mysore trumpetvine History & registers
Where this page came from built 2026-09-20 · dossier v2 · node
gbif.species answeredcarried from build of 2026-09-19 (offline re-derivation; the backbone was not asked)gbif.synonyms answeredcarried from build of 2026-09-19 (offline re-derivation; the backbone was not asked)gbif.vernacular answeredcarried from build of 2026-09-19 (offline re-derivation; the backbone was not asked)wcvp.distribution answeredgbif.occurrences answeredGBIF occurrence download https://doi.org/10.15468/dl.3h4zamclimate answeredwikidata answeredcarried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)wikipedia answeredcarried from build of 2026-09-19; this build: skippedinat.taxon not askedinat.photos.wild answeredcarried from build of 2026-09-19; this build: skippedinat.photos.cultivated nothing to reportcarried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)commons nothing to reportcarried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)gbif.media answeredopenalex answeredcarried from build of 2026-09-19; this build: skippedEvery upstream is recorded as having answered, reported nothing, or refused. Only “nothing to report” is ever shown as an absence. Records came from 100 datasets via GBIF.org; each carries its own licence.








