Hypericum humifusumL.

trailing St John's-worttrailing St. Johnswort

WFO wfo-0000727753 Accepted WFO 2026-06 8 photographs CC0 / CC BY / CC BY-SA

Plate 1 figs. a–h · 8 separate observations

Hypericum humifusum, photographed by Piermario Maculan
fig. a Piermario Maculan, CC0 1.0 / 2022-06-11 / obs. 205270780

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 27 botanical countries

Regions where Hypericum humifusum is native: Algeria, Azores, Canary Is., Madeira, Morocco, Albania, Austria, Belarus, Belgium, Corse, Czechia-Slovakia, Denmark, France, Germany, Great Britain, Hungary, Ireland, Italy, Netherlands, NW. Balkan Pen., Poland, Portugal, Romania, Spain, Sweden, Switzerland, Ukraine AlgeriaMoroccoAlbaniaAustriaBelarusBelgiumCorseCzechia-SlovakiaDenmarkFranceGermanyHungaryIrelandItalyNetherlandsNW. Balkan Pen.PolandPortugalRomaniaSpainSwedenSwitzerlandUkraine AzoresCanary Is.Madeira
Native distribution of Hypericum humifusum, 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
Albania ALB EUROPE
Austria AUT
Belarus BLR
Belgium BGM
Corse COR
Czechia-Slovakia CZE
Denmark DEN
France FRA
Germany GER
Great Britain GRB
Hungary HUN
Ireland IRE
Italy ITA
Netherlands NET
NW. Balkan Pen. YUG
Poland POL
Portugal POR
Romania ROM
Spain SPA
Sweden SWE
Switzerland SWI
Ukraine UKR
Algeria ALG AFRICA
Azores AZO
Canary Is. CNY
Madeira MDR
Morocco MOR

Not drawn on the map: Great Britain. We hold no public-domain boundary for this region, so it is 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 351 in flower of 360 examined

Proportion of examined Hypericum humifusum in flower, by month
Month In flower Examined Share 95% interval
Jan 7 8 88% 53% to 98%
Feb 9 10 90% 60% to 98%
Mar 3 3 too few examined
Apr 17 17 100% 82% to 100%
May 94 96 98% 93% to 99%
Jun 95 95 100% 96% to 100%
Jul 33 34 97% 85% to 99%
Aug 44 46 96% 85% to 99%
Sep 20 21 95% 77% to 99%
Oct 15 16 94% 72% to 99%
Nov 8 8 100% 68% to 100%
Dec 6 6 100% 61% to 100%

Peak flowering in Apr. Each bar is the share of Hypericum humifusum 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. 351 of 360 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. One month has fewer than 5 examined observations, so no proportion is drawn for it. 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 1,725 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -5.3 °C 1.9 °C 12.9 °C
Warmest month, mean daily high 17.5 °C 22.4 °C 28.3 °C
Annual rainfall 676 mm 1,099 mm 2,019 mm
Rainfall in the driest quarter 72 mm 160 mm 314 mm

It is found where winters bring hard frost. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 1,725 research-grade observations of Hypericum humifusum 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 27 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.

  • Holosepalum humifusum (L.) Fourr.
  • Hypericum decumbens Peterm.
  • Hypericum exiguum Bubani
  • Hypericum humifusum f. crassum Pugsley
  • Hypericum humifusum f. eglandulosum Pugsley
  • Hypericum humifusum f. laxum Pugsley
  • Hypericum humifusum f. liottardii (Vill.) Rouy
  • Hypericum humifusum subsp. liottardii (Vill.) Bonnier
  • Hypericum humifusum subvar. adscendens Neyraut
  • Hypericum humifusum var. ambiguum Gillot
  • Hypericum humifusum var. australe Willk.
  • Hypericum humifusum var. australe Lange
  • Hypericum humifusum var. calycinum Willk.
  • Hypericum humifusum var. decumbens (Peterm.) Rchb.
  • Hypericum humifusum var. glandulosum Wallr.
  • Hypericum humifusum var. liottardii (Vill.) Vill.
  • Hypericum humifusum var. liottardii (Vill.) Choisy
  • Hypericum humifusum var. losae (Sennen ex Losa) Sennen
  • Hypericum humifusum var. magnum Bastard
  • Hypericum humifusum var. majus Rouy
  • Hypericum humifusum var. nanum Gaudin
  • Hypericum humifusum var. pumilum Klett & Richt.
  • Hypericum humifusum var. radicans Neyraut
  • Hypericum liottardii Vill.

and 3 more.

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.