Kalmia procumbens(L.) Gift, Kron & P.F.Stevens ex Galasso, Banfi & F.Conti

Trailing Azaleaalpine azaleaalpine-azaleatrailing azalea

WFO wfo-0001280881 Accepted WFO 2026-06 8 photographs CC BY / CC BY-SA

Plate 1 figs. a–h · 8 separate observations

Kalmia procumbens, photographed by F Quiec
fig. a F Quiec, CC BY-SA 4.0 / 2022-06-11 / obs. 205679441
Kalmia procumbens, photographed by Elias
fig. b Elias, CC BY 4.0 / obs. 204943837
Kalmia procumbens, photographed by Matt Muir
fig. c Matt Muir, CC BY 4.0 / obs. 202083940
Kalmia procumbens, photographed by Philipp
fig. d Philipp, CC BY 4.0 / obs. 201483127
Kalmia procumbens, photographed by Erin McKittrick
fig. e Erin McKittrick, CC BY 4.0 / obs. 201435259
Kalmia procumbens, photographed by Todd Boland
fig. f Todd Boland, CC BY 4.0 / obs. 199790461
Kalmia procumbens, photographed by Andrew Melton
fig. g Andrew Melton, CC BY 4.0 / obs. 159911260
Kalmia procumbens, photographed by Junichi　Mandai
fig. h Junichi　Mandai, CC BY 4.0 / obs. 150621532

Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.

Native range 47 botanical countries

Regions where Kalmia procumbens is native: Chita, Irkutsk, Japan, Kamchatka, Khabarovsk, Krasnoyarsk, Kuril Is., Magadan, Primorye, Sakhalin, West Siberia, Yakutiya, Austria, Finland, Føroyar, France, Germany, Great Britain, Iceland, Italy, North European Russia, Norway, NW. Balkan Pen., Romania, Spain, Sweden, Switzerland, Ukraine, Alaska, Alberta, Aleutian Is., British Columbia, Greenland, Labrador, Maine, Manitoba, New Hampshire, New York, Newfoundland, Northwest Territories, Nunavut, Ontario, Québec, Saskatchewan, Washington, Wyoming, Yukon ChitaIrkutskJapanKamchatkaKhabarovskKrasnoyarskMagadanPrimoryeSakhalinWest SiberiaYakutiyaAustriaFinlandFranceGermanyIcelandItalyNorth European RussiaNorwayNW. Balkan Pen.RomaniaSpainSwedenSwitzerlandUkraineAlaskaAlbertaBritish ColumbiaGreenlandLabradorMaineManitobaNew HampshireNew YorkNewfoundlandNorthwest TerritoriesNunavutOntarioQuébecSaskatchewanWashingtonWyomingYukon Føroyar
Native distribution of Kalmia procumbens, after Kew’s World Checklist of Vascular Plants. Introduced, extinct and doubtful records are excluded, so this is where the plant is from, not everywhere it now grows. Regions too small to draw at this scale are marked with a dot.
RegionTDWG codeContinent
Alaska ASK NORTHERN AMERICA
Alberta ABT
Aleutian Is. ALU
British Columbia BRC
Greenland GNL
Labrador LAB
Maine MAI
Manitoba MAN
New Hampshire NWH
New York NWY
Newfoundland NFL
Northwest Territories NWT
Nunavut NUN
Ontario ONT
Québec QUE
Saskatchewan SAS
Washington WAS
Wyoming WYO
Yukon YUK
Austria AUT EUROPE
Finland FIN
Føroyar FOR
France FRA
Germany GER
Great Britain GRB
Iceland ICE
Italy ITA
North European Russia RUN
Norway NOR
NW. Balkan Pen. YUG
Romania ROM
Spain SPA
Sweden SWE
Switzerland SWI
Ukraine UKR
Chita CTA ASIA-TEMPERATE
Irkutsk IRK
Japan JAP
Kamchatka KAM
Khabarovsk KHA
Krasnoyarsk KRA
Kuril Is. KUR
Magadan MAG
Primorye PRM
Sakhalin SAK
West Siberia WSB
Yakutiya YAK

Not drawn on the map: Kuril Is., Great Britain, Aleutian Is.. We hold no public-domain boundary for these regions, so they are listed rather than guessed at.

Region boundaries approximated from Natural Earth (public domain) and mapped to TDWG World Geographical Scheme for Recording Plant Distributions (WGSRPD) level-3 botanical countries (Brummitt 2001). Indicative, not the official WGSRPD geometry.

Flowering 1,039 in flower of 1,338 examined

Peak flowering in Jun. Each bar is the share of Kalmia procumbens observations in which someone actually recorded the reproductive state and found the plant in flower, not the raw number of flowering records. That distinction matters: people observe plants far more in spring than in winter, so a bare count of flowering records partly measures when people go outside. Dividing by the number examined removes that. 1,039 of 1,338 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 6 months have fewer than 5 examined observations, so no proportion is drawn for them. This is still a global aggregate and not a forecast for your garden: the same species flowers on different dates in different hemispheres. Where a species has fewer than 30 flowering records we do not draw this chart at all. Computed from 10.15468/dl.cgje2x.

Where it actually grows measured, from 1,968 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -24.2 °C -14.6 °C 1.5 °C
Warmest month, mean daily high 10.7 °C 14.4 °C 18.3 °C
Annual rainfall 616 mm 1,469 mm 3,642 mm
Rainfall in the driest quarter 69 mm 228 mm 511 mm

It is found where winters are severely cold. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 1,968 research-grade observations of Kalmia procumbens that carry a coordinate, and this is the range those places actually span. The 5th and 95th percentiles are used rather than the minimum and maximum, because a single cultivated specimen in a heated conservatory should not widen a tropical plant's range to the Arctic.

This is not a hardiness zone. A USDA zone is the average annual extreme minimum temperature. The figure above is the mean daily minimum of the coldest month, which is a different quantity and is typically far warmer. Reading one as the other would place a plant several zones too warm, so we do not publish a hardiness zone, because we do not have one. Climate from CHELSA V2.1 (Karger et al. 2017); occurrences from 10.15468/dl.cgje2x.

Also published as 7 synonyms

A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.

  • Azalea procumbens L.
  • Chamaecistus procumbens (L.) Kuntze
  • Chamaecistus serpyllifolius Gray
  • Chamaeledon procumbens (L.) Link
  • Loiseleuria procumbens (L.) Loisel.
  • Loiseleuria procumbens (L.) Desv.
  • Rhododendron procumbens (L.) E.H.L.Krause

Sourcesevery claim on this page

  1. World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
  2. iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
  3. Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
  4. Kew, World Checklist of Vascular Plants (WCVP v16). native distribution by TDWG level-3 botanical country, and life form. CC BY 3.0. Retrieved 2026-06-04.

We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite.