106 photographs › At a glance
- Jan
- Feb
- Mar
- Apr
- May, shaded
- Jun, shaded
- Jul, shaded
- Aug, shaded
- Sep, shaded
- Oct, shaded
- Nov
- Dec
From few records: 6 records in 6 grid cells. The records.
Summary
Asclepias prostrata, commonly known as prostrate milkweed, is a species of perennial plant in the genus Asclepias. It has triangular to elliptical foliage with wavy margins, stems up to 16 inches (410 mm) long, and grows low to the ground (hence the name, which refers to a prostrate growth habit) in sandy soils. Flowering may be dependent on rainfall to bring the plant out of dormancy, but is most typical from April to October. Like other milkweeds, A. prostrata flowers are a food source for pollinator insects such as bees, wasps, and the Monarch butterfly.
Quoted from Wikipedia, "Asclepias prostrata", CC BY-SA 4.0.
About the genus · Asclepias
Asclepias is a genus of herbaceous, perennial, flowering plants known as milkweeds, named for their latex, a milky substance containing cardiac glycosides termed cardenolides, exuded where cells are damaged. Most species are toxic to humans and many other species, primarily due to the presence of cardenolides. However, as with many such plants, some species feed upon milkweed leaves or the nectar from their flowers. More on Wikipedia ›
Quoted from Wikipedia, "Asclepias", CC BY-SA 4.0.
Cultivation
Seasons
The rain rule reads a summer growing season: 70% of the median year's rain (557 mm of 739 mm) falls in May to October, warmer than the year (wet-season mean 27.2 °C against a yearly mean of 23.6 °C). Months are the habitat's, northern hemisphere; shifted six months for a southern-hemisphere collection: November to April.
Rain
739 mm in the median year at the habitat, 557 mm of it May to October. Wettest month September at 147 mm, driest month March at 21 mm. Across the grid cells of the range the year's total runs 578 mm to 784 mm, the 10th to 90th percentile of each cell's own year. The median of the cells' own yearly totals, 737 mm, is the year's rain at the top of the page; the 739 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: 21 to 42 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 20, the highest 90th-percentile month 44).
Warmth and air
Coldest: the 1st-percentile night over 44 years at a typical spot in the range is 4.2 °C, the absolute minimum -6.9 °C, 24 frost nights in 44 years (NASA POWER daily minima). Warmest: the 99th-percentile day is 39.9 °C. Monthly means: the coldest month's mean nightly low 14.0 °C in January (across the grid cells of the range 11.6 °C to 14.8 °C), the warmest month's mean daily high 32.8 °C in August (median year across the grid cells of the range, CHELSA). Cold floor: 4.2 °C, which is the 1st-percentile night over 44 years at a typical spot in the range (NASA POWER).
Relative humidity at the habitat: 61 to 65% 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 -45 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
From few records: this habitat climate is read from 6 records in 6 grid cells; a page says so under 12 records or 5 cells, and shows the figures as read.
Habitat months, northern hemisphere
Mean daily high from 22 °C in Jan to 33 °C in Aug; mean nightly low from 14 °C in Jan to 25 °C in Jun, Jul and Aug. The cold quarter, Dec to Feb, is the three months around the coldest month's mean nightly low. 739 mm of rain in the median year (the twelve monthly medians added), the wettest month Sep. The bands show the 10th to 90th percentile across 6 habitat cells. Over 44 years at a typical spot in the range (NASA POWER) the absolute minimum was -6.9 °C and the 99th-percentile day 39.9 °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 | 22 / 22–23 | 24 / 24–25 | 27 / 26–28 | 30 / 29–31 | 31 / 30–34 | 32 / 31–35 | 32 / 31–36 | 33 / 32–36 | 31 / 30–33 | 28 / 28–30 | 26 / 25–26 | 23 / 22–24 |
| Night °C | 14 / 12–15 | 15 / 13–16 | 18 / 16–19 | 21 / 19–21 | 23 / 23–24 | 25 / 24–25 | 25 / 24–25 | 25 / 24–26 | 24 / 23–24 | 21 / 20–22 | 18 / 16–19 | 15 / 12–16 |
| Rain mm | 30 / 28–35 | 23 / 21–23 | 21 / 18–24 | 51 / 42–52 | 67 / 64–70 | 90 / 65–98 | 101 / 68–108 | 83 / 57–90 | 147 / 102–161 | 69 / 58–75 | 28 / 23–30 | 29 / 24–32 |
| DLI | 22 / 21–22 | 26 / 26–27 | 33 / 32–33 | 38 / 38–38 | 40 / 40–40 | 42 / 41–43 | 42 / 42–44 | 41 / 41–42 | 34 / 34–35 | 30 / 29–30 | 25 / 24–25 | 21 / 20–21 |
| RH % | 61 / 58–62 | 62 / 57–63 | 61 / 56–62 | 62 / 56–63 | 63 / 58–65 | 64 / 58–65 | 63 / 57–64 | 63 / 57–64 | 65 / 59–66 | 63 / 58–63 | 61 / 57–62 | 61 / 58–62 |
How this section is made
Natural habitat
How this section is made
Photographs
Photographs: (c) Turner Brockman, some rights reserved (CC BY-SA) (5); (c) Cody Stricker, 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.
Manihot walkerae Walker's manioc Photo: CC BY-SA, Turner Brockman
Sideroxylon celastrinum Coma Photo: CC BY, Tom Field
Citharexylum berlandieri Berlandier's fiddlewood Photo: CC BY, Katie Raney
Ebenopsis ebano Texas ebony Photo: CC BY, Justin Quintanilla
Celosia nitida West Indian cock's comb Photo: CC BY, johnyochum
Amyris texana Texas torchwood Photo: CC BY, Michelle W. （鍾偉瑋）Other Asclepias 48 in the reference
Asclepias albicans White-Stem milkweed Photo: CC BY, Matt Berger
Asclepias amplexicaulis Blunt-leaf milkweed Photo: CC0, author not stated
Asclepias angustifolia Arizona milkweed Photo: CC BY, Cheng-Te Hsu
Asclepias asperula Antelope horns Photo: CC BY, Parker James Lloyd
Asclepias brachystephana Shortcrown milkweed Photo: CC BY, Cody Hinchliff
Asclepias californica California milkweed Photo: CC BY, klicklo
Asclepias cordifolia Purple milkweed Photo: CC BY-SA, Brian Finzel
Asclepias cryptoceras Humboldt Mountains milkweed Photo: CC BY, Parker James Lloyd
Asclepias curassavica Bloodflower Photo: CC BY, Ricard Busquets Reverte
Asclepias engelmanniana Engelmann's milkweed Photo: CC BY, Rajan Rao
Asclepias eriocarpa Indian milkweed Photo: CC BY, klicklo
Asclepias erosa Desert milkweed Photo: CC BY, CK2AZ all 49 ›Names & registers
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 2026-10-21
gbif.species answeredasked 2026-10-21gbif.synonyms answeredasked 2026-10-21gbif.vernacular answeredasked 2026-10-21names fetched 2026-10-21wcvp.distribution answeredas of 2026-06-04gbif.occurrences answeredas of 2026-10-21GBIF occurrence download https://doi.org/10.15468/dl.hbdw64, of 2026-10-21climate answeredasked 2026-10-21climate.extremes answeredasked 2026-10-21NASA POWER (MERRA-2) daily 1981–2024, cell 24.50_-98.125, lapse-corrected -45 m at 6.5 °C/kmwikidata answeredasked 2026-10-21wikipedia answeredasked 2026-10-21inat.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 2026-10-21openalex 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 8 datasets via GBIF.org; each carries its own licence.