Example ⟳ +
An example collection, so you can see what this page does. Nothing added here is kept: leaving deletes it.
Asclepias albicans; photograph (c) Ian McFaul, some rights reserved (CC BY) CC BY(c) Ian McFaul, some rights reserved (CC BY) · observed growing wild · 2026-04-30

Asclepias albicans S.Watson

White-Stem milkweed; Wax milkweed; Candelilla; Giant cane milkweed

Apocynaceae · Arizona, California +1

Add one to my plants
Sow seed
Asclepias albicans, photograph (c) Matt Berger, some rights reserved (CC BY)Asclepias albicans, photograph (c) Jose Luis Leon de la Luz, some rights reserved (CC BY)Asclepias albicans, photograph (c) Jose Luis Leon de la Luz, some rights reserved (CC BY)Asclepias albicans, photograph (c) Jose Luis Leon de la Luz, some rights reserved (CC BY)Asclepias albicans, photograph (c) Abraham Sánchez Romero, some rights reserved (CC BY)Asclepias albicans, photograph (c) Abraham Sánchez Romero, some rights reserved (CC BY) 102 photographs ›
Habitat figures
Cold floor (1 night in 100)
4.8°C
Record low 0.9 °C in 44 years, at a typical spot in the range NASA POWER
Warmest month, mean daily high
38°C
Jul at the habitat CHELSA
Rain a year (median across the range)
125mm
No month of 25 mm or more in the median year CHELSA
Open-sky light
21–55DLI
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
113 mm of rain in the median year, under the rule's 120 mm, so no rainy season is read; the cooler six months are November to April. rain and temperature rules, CHELSA
Northern hemisphere unless you set your site. The chart is in the habitat's months.

Summary

Asclepias albicans is a species of milkweed known by the common names whitestem milkweed and wax milkweed. It is native to the Mojave and Sonoran Deserts of California, Arizona, and Baja California. This is a spindly erect shrub usually growing 1 to 3 meters (3+1⁄2 to 10 feet) tall, but known to approach 4 metres (13 feet). The sticklike branches are mostly naked, the younger ones coated in a waxy residue and a thin layer of woolly hairs. More on Wikipedia ›

Quoted from Wikipedia, "Asclepias albicans", 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

Rain at the habitat is 113 mm in the median year (across the grid cells of the range, CHELSA). Under 120 mm the rain rule reads no rainy season, and the growing-season rule infers nothing from it. The temperature rule reads the cooler six months as November to April. Months are the habitat's, northern hemisphere; shifted six months for a southern-hemisphere collection: May to October.

Rain

113 mm in the median year at the habitat. Wettest month January at 17 mm, driest months (2 at 1 mm); 3 months under 5 mm. Across the grid cells of the range the year's total runs 79 mm to 236 mm, the 10th to 90th percentile of each cell's own year. The median of the cells' own yearly totals, 125 mm, is the year's rain at the top of the page; the 113 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 55 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 55).

Warmth and air
Temperature

Coldest: the 1st-percentile night over 44 years at a typical spot in the range is 4.8 °C, the absolute minimum 0.9 °C, no frost in 44 years (NASA POWER daily minima). Warmest: the 99th-percentile day is 34.1 °C. Monthly means: the coldest month's mean nightly low 7.9 °C in December (across the grid cells of the range 5.1 °C to 15.7 °C), the warmest month's mean daily high 38.3 °C in July (median year across the grid cells of the range, CHELSA). Cold floor: 4.8 °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: 39 to 46% 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 +331 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, northern hemisphere

Habitat climate of Asclepias albicans through the yearWarmest month July, mean daily high 38 °C; coldest month December, mean nightly low 7.9 °C; 113 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, northern hemisphere.-10°0°10°20°30°40°50°frost34.1° 99th-percentile day, NASA POWER0.9° lowest night in 44 years, NASA POWER°C · day and nightcold quarter0102030405060mm rainDLI 21–55RH 39–46%JanFebMarAprMayJunJulAugSepOctNovDec
day night rain medians and 10th–90th percentile across 339 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 °C19 / 17–2121 / 18–2324 / 21–2627 / 24–3032 / 27–3536 / 31–3938 / 32–4237 / 32–4135 / 31–3829 / 27–3224 / 21–2519 / 16–22
Night °C8 / 5–159 / 7–1512 / 9–1614 / 11–1818 / 15–2122 / 18–2526 / 22–2826 / 22–2824 / 20–2718 / 15–2312 / 9–198 / 5–16
Rain mm17 / 9–3415 / 7–3712 / 3–303 / 1–101 / 0–31 / 0–17 / 4–1715 / 8–3811 / 7–568 / 6–158 / 6–1615 / 12–29
DLI24 / 22–2830 / 28–3439 / 38–4248 / 47–4953 / 52–5355 / 52–5550 / 47–5146 / 44–4741 / 39–4234 / 32–3625 / 24–2921 / 20–25
RH %46 / 43–5546 / 42–5344 / 40–5242 / 37–5041 / 36–5139 / 34–5242 / 38–5444 / 40–5643 / 39–5742 / 39–5444 / 40–5446 / 43–55
How this section is made
Each figure is the median across the 339 grid cells on land that hold in-range records (865 records in those cells; 8 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 1215:1317 (29.225, -114.125). Over 44 years there: absolute minimum 0.9 °C, 1st-percentile night 4.8 °C, 99th-percentile day 34.1 °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 339 distinct grid cells holding 865 of the 877 in-range records (8 further cells with records at sea, by the elevation layer, left out); extremes and elevation at the typical cell 1215:1317 (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 29.00_-114.375, lapse-corrected +331 m at 6.5 °C/km. Elevation: ETOPO 2022, 599 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.
NativeArizona, California, Mexico Northwest · 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 marker32.991, -116.112 · in the densest population, 790 records (72% of those in range)
Kew's description“subshrub or shrub” · “desert or dry shrubland” · quoted from WCVP, RBG Kew (CC BY 4.0); not derived here
Evidence usedThe map marker rests on all 1099 georeferenced records inside the native range; the climate across the range on the 865 of them in the land cells it reads, of 877 placed to within 10 km; the map shows only the 438 openly licensed ones, which alone would put the marker 31 km away. 222 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 of the 1099 in-range records; it decides nothing. Records outside the native range, living specimens and records marked introduced are not used; which records count.

Photographs

Asclepias albicans, photograph 1did not loadAsclepias albicans, photograph 2did not loadAsclepias albicans, photograph 3did not loadAsclepias albicans, photograph 4did not loadAsclepias albicans, photograph 5did not loadAsclepias albicans, photograph 6did not load

Photographs: (c) Matt Berger, some rights reserved (CC BY); (c) Jose Luis Leon de la Luz, some rights reserved (CC BY) (3); (c) Abraham Sánchez Romero, some rights reserved (CC BY) (2).

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

Cylindropuntia munzii Cylindropuntia munzii Munz cholla Photo: CC0, author not statedBrandegea bigelovii Brandegea bigelovii Cucurbitaceae Photo: CC BY-SA, joedecruyenaereAchyronychia cooperi Achyronychia cooperi Cooper's frostmat Photo: CC BY, Matt BergerAsclepias subulata Asclepias subulata Rush milkweed Photo: CC0, author not statedLupinus arizonicus Lupinus arizonicus Arizona lupine Photo: CC BY, Matt BergerChylismia cardiophylla Chylismia cardiophylla Heartleaf suncup Photo: CC BY, Matt Berger

Other Asclepias 48 in the reference

Asclepias amplexicaulis Asclepias amplexicaulis Blunt-leaf milkweed Photo: CC0, author not statedAsclepias angustifolia Asclepias angustifolia Arizona milkweed Photo: CC BY, Cheng-Te HsuAsclepias asperula Asclepias asperula Antelope horns Photo: CC BY, Parker James LloydAsclepias brachystephana Asclepias brachystephana Shortcrown milkweed Photo: CC BY, Cody HinchliffAsclepias californica Asclepias californica California milkweed Photo: CC BY, klickloAsclepias cordifolia Asclepias cordifolia Purple milkweed Photo: CC BY-SA, Brian FinzelAsclepias cryptoceras Asclepias cryptoceras Humboldt Mountains milkweed Photo: CC BY, Parker James LloydAsclepias curassavica Asclepias curassavica Bloodflower Photo: CC BY, Ricard Busquets ReverteAsclepias engelmanniana Asclepias engelmanniana Engelmann's milkweed Photo: CC BY, Rajan RaoAsclepias eriocarpa Asclepias eriocarpa Indian milkweed Photo: CC BY, klickloAsclepias erosa Asclepias erosa Desert milkweed Photo: CC BY, CK2AZAsclepias exaltata Asclepias exaltata Poke milkweed Photo: CC BY, Jaime McGuigan all 49 ›

Names & registers

GBIFPOWOIPNIWFOWikidataWikipediaiNaturalist

The record

Family
Apocynaceae
Described by
S.Watson
Native to
Arizona, California, Mexico Northwest
Wild records
1099 in range · 438 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 2026-10-21
GBIF species record gbif.species answeredasked 2026-10-21
GBIF synonyms gbif.synonyms answeredasked 2026-10-21
GBIF common names gbif.vernacular answeredasked 2026-10-21names fetched 2026-10-21
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
Habitat climate climate answeredasked 2026-10-21
Daily extremes (NASA POWER) climate.extremes answeredasked 2026-10-21NASA POWER (MERRA-2) daily 1981–2024, cell 29.00_-114.375, lapse-corrected +331 m at 6.5 °C/km
Wikidata wikidata answeredasked 2026-10-21
Wikipedia wikipedia answeredasked 2026-10-21
iNaturalist photographs, wild inat.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 2026-10-22
iNaturalist photographs, cultivated inat.photos.cultivated not asked
GBIF media gbif.media answeredasked 2026-10-21
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 64 datasets via GBIF.org; each carries its own licence.

Cultifolio

Opening your plants…