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Rhododendron baileyi Balf.f.

Ericaceae · China South-Central, Tibet +1 · listed by its genus as a temperate garden plant

Cited as Kew's World Checklist cites it, Rhododendron baileyi Balf.f.: GBIF's backbone key for this page carries the name with another author, Balf.fil.

Photographs not checked iNaturalist was skipped (not asked) when this page was built. Not asked, or not answered, is not "none": nothing here claims there is none. Why the site says it this way.
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Sow seed
Habitat figuresfrom few records
Coldest month, mean nightly low
-10.6°C
Jan at the habitat, not a floor; extremes not used (the weather cell's ground is too far off) CHELSA
Warmest month, mean daily high
14°C
Jul and Aug at the habitat CHELSA
Rain a year (median across the range)
1,833mm
10 months of 25 mm or more in the median year CHELSA
Open-sky light
22–36DLI
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 June to September, read as a summer growing season. rain rule, CHELSA
Northern hemisphere unless you set your site. The chart is in the habitat's months.

From few records: 3 records in 3 grid cells. The records.

About the genus · Rhododendron

Rhododendron, from Ancient Greek ῥόδον (rhódon), meaning "rose", and δένδρον (déndron), meaning "tree", is a very large genus of about 1,024 species of woody plants in the heath family (Ericaceae). They can be either evergreen or deciduous. Most species are native to eastern Asia and the Himalayan region, but smaller numbers occur elsewhere in Asia, and in North America, Europe and Australia.

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

Cultivation

Grouped as a temperate garden plant, listed under the genus Rhododendron in the archetype table, and Kew describes it as “shrub”, “subalpine or subarctic”.

Seasons

The rain rule reads a summer growing season: 70% of the median year's rain (1,314 mm of 1,837 mm) falls in June to September, warmer than the year (wet-season mean 10.0 °C against a yearly mean of 3.5 °C). Months are the habitat's, northern hemisphere; shifted six months for a southern-hemisphere collection: December to March.

Rain

1,837 mm in the median year at the habitat, 1,314 mm of it June to September. Wettest month July at 465 mm, driest month December at 19 mm. Across the grid cells of the range the year's total runs 1,811 mm to 2,644 mm, the 10th to 90th percentile of each cell's own year. The median of the cells' own yearly totals, 1,833 mm, is the year's rain at the top of the page; the 1,837 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: 22 to 36 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 21, the highest 90th-percentile month 37).

Warmth and air
Temperature

Monthly means: the coldest month's mean nightly low -10.6 °C in January (across the grid cells of the range -12.5 °C to -10.5 °C), the warmest month's mean daily high 13.6 °C in August (median year across the grid cells of the range, CHELSA). Cold floor: none read. The nearest figure is -10.6 °C, the coldest month's mean nightly low, January, in the median year (CHELSA); a month's mean of its nightly lows is warmer than the nights a floor is read from. The daily extremes were read at a weather cell whose ground is too far above or below the typical spot to correct for, and are not used.

Humidity

Relative humidity at the habitat: 61 to 77% 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. CHELSA monthly means, median year across the grid cells of the range. No cold floor is read without a daily extremes series; the coldest month's mean nightly low named in its sentence is not one. 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 Rhododendron in the archetype table, and Kew describes it as “shrub”, “subalpine or subarctic”. 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

From few records: this habitat climate is read from 3 records in 3 grid cells; a page says so under 12 records or 5 cells, and shows the figures as read.

Habitat months, northern hemisphere

Habitat climate of Rhododendron baileyi through the yearWarmest months July and August, mean daily high 14 °C; coldest month January, mean nightly low -10.6 °C; 1,837 mm of rain in the median year (the twelve monthly medians added). Medians across the range, from CHELSA. Habitat months, northern hemisphere.-15°-10°-5°0°5°10°15°frost°C · day and nightcold quarter0100200300400500600mm rainDLI 22–36RH 61–77%JanFebMarAprMayJunJulAugSepOctNovDec
day night rain medians and 10th–90th percentile across 3 habitat cells, CHELSA cold quarter: the three months around the coldest month's mean nightly low DLI, mol/m²/dayRH %each on its own scale
Figures by month
JanFebMarAprMayJunJulAugSepOctNovDec
Day °C-1 / -3–00 / -2–13 / 1–47 / 5–811 / 9–1113 / 12–1314 / 12–1414 / 12–1412 / 11–129 / 7–94 / 3–51 / -1–2
Night °C-11 / -13–-11-9 / -11–-9-6 / -7–-6-3 / -4–-21 / 0–26 / 4–67 / 6–87 / 6–75 / 4–50 / -1–0-5 / -6–-4-8 / -11–-8
Rain mm27 / 27–4449 / 49–9573 / 72–13098 / 96–198141 / 139–255264 / 259–381465 / 454–577345 / 343–413240 / 238–32792 / 91–15824 / 23–3819 / 18–29
DLI24 / 24–2429 / 28–2934 / 31–3436 / 34–3734 / 33–3528 / 27–2922 / 21–2324 / 23–2525 / 25–2626 / 26–2723 / 23–2422 / 22–22
RH %62 / 60–6265 / 63–6770 / 68–7170 / 69–7171 / 70–7174 / 73–7577 / 76–7776 / 74–7674 / 72–7467 / 67–6864 / 63–6461 / 59–62

The daily extremes were not used: the correction for elevation, +1176 m, is beyond the 1,000 m either way that a lapse rate is applied over, so the weather cell's ground is other terrain than the typical spot's. So no cold floor is read for this species, and the coldest month's mean nightly low is not taken as one. What that cell gave, so corrected, over 44 years: absolute minimum -17.1 °C, 1st-percentile night -12.4 °C.

How this section is made
Each figure is the median across the 3 grid cells holding the 3 in-range records, 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 1251:5419 (27.425, 90.975). 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 3 distinct grid cells holding 3 of the 3 in-range records; extremes and elevation at the typical cell 1251:5419 (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 27.50_91.250, lapse-corrected +1176 m at 6.5 °C/km. Elevation: ETOPO 2022, 3595 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.
NativeChina South-Central, Tibet, East Himalaya · 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 marker27.634, 90.254 · in the densest population, 5 records (83% of those in range)
Kew's description“shrub” · “subalpine or subarctic” · quoted from WCVP, RBG Kew (CC BY 4.0); not derived here
Evidence usedThe map marker rests on all 6 georeferenced records inside the native range; the climate across the range on the 3 of them placed to within 10 km; the map shows only the 3 openly licensed ones, which alone would put the marker 40 km away. 1 record outside the WCVP native range not used. Under a dozen records behind the map and the climate. 3 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 6 in-range records; it decides nothing. Records outside the native range, living specimens and records marked introduced are not used; which records count.

Photographs

Not checked. iNaturalist was skipped (not asked) when this page was built; GBIF's observation records with coordinates hold none. Not a statement that none exist.

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

Primula capitata Primula capitata Buttonhead primrose Photo: CC BY, V_NebenfuehrRhododendron lepidotum Rhododendron lepidotum Scaly rhododendron Photo: CC0, author not statedPrunus rufa Prunus rufa Himalayan Cherry Photo: CC BY, Siddarth MachadoCyananthus lobatus Cyananthus lobatus Campanulaceae Photo: CC BY, V_NebenfuehrGentiana elwesii Gentiana elwesii Gentianaceae Photo: CC BY, Morten RossRhododendron lanatum Rhododendron lanatum Ericaceae Photo: CC BY, Morten Ross

Other Rhododendron 574 in the reference

Rhododendron aberconwayi Rhododendron aberconwayi Ericaceae Photo: Public domain, Daderot Rhododendron abietifolium Ericaceae Rhododendron acrophilum Ericaceae Rhododendron adamsii Rhododendron adamsii Sagan Dalya Photo: CC BY, Valentin KosterinRhododendron adenogynum Rhododendron adenogynum Ericaceae Photo: CC BY-SA, Kurt StüberRhododendron adenopodum Rhododendron adenopodum Ericaceae Photo: CC BY-SA, Ulf EliassonRhododendron adenosum Rhododendron adenosum Ericaceae Photo: CC0, DaderotRhododendron aeruginosum Rhododendron aeruginosum Ericaceae Photo: CC BY, Siddarth MachadoRhododendron aganniphum Rhododendron aganniphum Ericaceae Photo: CC0, Daderot Rhododendron agathodaemonis Ericaceae Rhododendron alabamense Rhododendron alabamense Alabama azalea Photo: CC BY, Rob JohnRhododendron albiflorum Rhododendron albiflorum White rhododendron Photo: CC0, author not stated all 575 ›

Names & registers

Also known as Rhododendron thyodocum. (GBIF Backbone)

GBIFPOWOIPNIWFOWikidata

The record

Family
Ericaceae
Described by
Balf.f.
Native to
China South-Central, Tibet, East Himalaya
Wild records
6 in range · 3 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 2026-10-22GBIF's key 5832240 is Rhododendron baileyi Balf.fil.; the page links Kew's Rhododendron baileyi Balf.f., and the name is cited as Kew cites it
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
Habitat climate climate answeredasked 2026-10-22
Daily extremes (NASA POWER) climate.extremes answeredasked 2026-10-22NASA POWER (MERRA-2) daily 1981–2024, cell 27.50_91.250, lapse-corrected +1176 m at 6.5 °C/km; read, and set aside: the correction for elevation, +1176 m, is beyond the 1,000 m either way that a lapse rate is applied over, so the weather cell's ground is other terrain than the typical spot's, so no cold floor is shown
Wikidata wikidata answeredasked 2026-10-22
Wikipedia wikipedia nothing to reportasked 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 nothing to reportasked 2026-10-22
Wikimedia Commons commons nothing to reportasked 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 5 datasets via GBIF.org; each carries its own licence.

Cultifolio

Opening your plants…