Silene undulata (Cape catchfly)

Plate 1 figs. a–h · 8 separate observations

Silene undulata, photographed by Nic Knott-Craig — fig. a Nic Knott-Craig, CC BY-SA 4.0 / 2022-03-26 / obs. 185001542

Silene undulata, photographed by Tony Rebelo — fig. b Tony Rebelo, CC BY-SA 4.0 / obs. 172648899

Silene undulata, photographed by linkie — fig. h linkie, CC BY 4.0 / obs. 162078327

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.

The specimen a real sheet, in a real collection

Herbarium: Royal Botanic Gardens, Kew
Accession: K005077816
Filed as: Silene undulata Aiton
Det. by: Masson, D.
Collected: Cooper Cole, J.
Origin: ZA
The sheet: View the digitised specimen (CC BY 4.0)

A real pressed plant, in a real collection, under the accession number above. Not an illustration of one. The holding institution does not serve this sheet’s image to third parties, so there is no photograph here. The record is real and the link goes to it. Where we hold no openly licensed sheet for a species this section is simply absent, and where a sheet never recorded who determined it, that field stays empty rather than being filled in. Roughly half of all herbarium sheets never recorded a determiner, which is ordinary.

Native range 8 botanical countries

Native distribution of Silene undulata, 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.

Region	TDWG code	Continent
Botswana	BOT	AFRICA
Cape Provinces	CPP
Eswatini	SWZ
Free State	OFS
KwaZulu-Natal	NAT
Lesotho	LES
Northern Provinces	TVL
Zimbabwe	ZIM

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 116 in flower of 128 examined

100%

70%

91%

88%

78%

86%

94%

97%

100%

86%

Proportion of examined Silene undulata in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	6	6	100%	61% to 100%
Feb	7	10	70%	40% to 89%
Mar	10	11	91%	62% to 98%
Apr	7	8	88%	53% to 98%
May	7	9	78%	45% to 94%
Jun	6	7	86%	49% to 97%
Jul	2	2	too few examined
Aug	2	2	too few examined
Sep	17	18	94%	74% to 99%
Oct	28	29	97%	83% to 99%
Nov	12	12	100%	76% to 100%
Dec	12	14	86%	60% to 96%

Peak flowering in Jan. Each bar is the share of Silene undulata 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. 116 of 128 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 2 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 515 observations

Condition	5th percentile	Median	95th percentile
Coldest month, mean daily low	0.1 °C	9.3 °C	13.0 °C
Warmest month, mean daily high	19.6 °C	23.5 °C	30.3 °C
Annual rainfall	349 mm	720 mm	1,226 mm
Rainfall in the driest quarter	19 mm	85 mm	200 mm

It is found where winters are cool but frost is light or absent. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 515 research-grade observations of Silene undulata 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 8 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.

Melandrium afrum (Fenzl ex Müll.Berol.) Rohrb.
Melandrium caffrum (Fenzl ex Müll.Berol.) Rohrb.
Melandrium undulatum subsp. afrum (Fenzl ex Müll.Berol.) Rohrb.
Melandrium undulatum var. caffrum (Fenzl ex Müll.Berol. ) Rohrb.
Melandrium undulatum var. capense (Otth) Rohrb.
Silene afra Fenzl ex Müll.Berol.
Silene caffra Fenzl ex Müll.Berol.
Silene capensis Otth

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.