Jacobaea maritima (Silver Ragwort)

Plate 1 figs. a–h · 8 separate observations

Jacobaea maritima, photographed by carnifex — fig. a carnifex, CC BY 4.0 / 2022-05-02 / obs. 193894386

Jacobaea maritima, photographed by Jon Sullivan — fig. b Jon Sullivan, CC BY 4.0 / obs. 195880088

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 13 botanical countries

Native distribution of Jacobaea maritima, 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.

Region	TDWG code	Continent
Corse	COR	EUROPE
France	FRA
Greece	GRC
Italy	ITA
NW. Balkan Pen.	YUG
Sardegna	SAR
Sicilia	SIC
Spain	SPA
Algeria	ALG	AFRICA
Morocco	MOR
Tunisia	TUN
East Aegean Is.	EAI	ASIA-TEMPERATE
Türkiye	TUR

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 259 in flower of 423 examined

50%

26%

11%

37%

70%

90%

71%

52%

50%

33%

40%

74%

Proportion of examined Jacobaea maritima in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	7	14	50%	27% to 73%
Feb	5	19	26%	12% to 49%
Mar	2	19	11%	3% to 31%
Apr	14	38	37%	23% to 53%
May	68	97	70%	60% to 78%
Jun	78	87	90%	81% to 94%
Jul	32	45	71%	57% to 82%
Aug	11	21	52%	32% to 72%
Sep	11	22	50%	31% to 69%
Oct	6	18	33%	16% to 56%
Nov	8	20	40%	22% to 61%
Dec	17	23	74%	54% to 87%

Peak flowering in Jun. Each bar is the share of Jacobaea maritima 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. 259 of 423 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 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 2,019 observations

Condition	5th percentile	Median	95th percentile
Coldest month, mean daily low	-0.4 °C	5.9 °C	11.3 °C
Warmest month, mean daily high	18.1 °C	25.2 °C	28.5 °C
Annual rainfall	541 mm	776 mm	1,585 mm
Rainfall in the driest quarter	26 mm	115 mm	223 mm

It is found where winters bring light 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 2,019 research-grade observations of Jacobaea maritima 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 23 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.

Cineraria acanthifolia Rchb.
Cineraria bicolor Willd.
Cineraria bicolor subsp. bicolor
Cineraria calvescens Nyman
Cineraria canadensis L.
Cineraria ceratophylla Ten.
Cineraria maritima (L.) L.
Othonna maritima L.
Senecio bicolor Tod.
Senecio bicolor subsp. bicolor
Senecio bicolor subsp. cineraria (DC.) Chater
Senecio cineraria DC.
Senecio cineraria subsp. bicolor (Willd.) Arcang.
Senecio cineraria subsp. cineraria
Senecio cineraria var. bicolor (Willd.) Caruel
Senecio cineraria var. cineraria
Senecio coronopifolius var. oasicolus Hochr.
Senecio erucaefolius Kunze
Senecio gibbosus subsp. bicolor (Willd.) Peruzzi, N.G.Passal. & Soldano
Senecio gibbosus subsp. cineraria (DC.) Peruzzi, N.G.Passal. & Soldano
Senecio ginesii Cuatrec.
Senecio maritimus (L.) Rchb.
Senecio willdenowii Peruzzi & N.G.Passal.

Sourcesevery claim on this page

World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
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.