The gray, feathery foliage of Jacobaea maritima.

A wild clump of Jacobaea maritima in flower, backed by the Mediterranean Sea.

Florists have discovered the large leaves of Jacobaea maritima 'Cirrus' and it is in high demand for new floral designs.

Jacobæa maritima (L.) Pelser & Meijden 2005

Asteraceæ • Asteroideæ • Senecioneæ • Senecioninæ

Has also been placed in Compositæ

Jacobaea : (see text) • maritima : maritimus - the sea, maritime, coastal area

dusty miller, cineraria ragwort, silver groundsel, silver ragwort • Català (Catalan): cinerària, donzell de mar • Español: cenicera marítima, cenicienta, cenizo, cineraria • Française: séneçon cinéraire • Italiano: senecione cinerario • Ελληνική (Greek): σινεράρια, σενέκιο

עברית (Hebrew): סביון מלבין

Native to the western, central, and eastern Mediterranean region, especially seaside cliffs and islands; now naturalised in various places such as the British Isles and New Zealand.

Though very common in horticulture, this plant has long been confused among botanists and horticulturists alike.  The former because variation and distribution of forms has led to differing conclusions by the various botanists trying to tackle its classification, and because the overall uncertainly of the taxon and its place within its family.  The latter because naming of it in horticulture has followed expediency rather than accuracy.  Inexplicably, this plant is sometimes represented on the web as Centaurea cineraria.

This new grouping under Jacobaea may seem to gardeners an unnecessary complication of the situation, but, in fact, it is an effort by today's botanists to acknowledge that this plant and its relations are distinct from the very large amd complex genus Senecio.  I have yet to trace the etymology of Jacobaea, but I have seen it in use for this plant (Jacobaea maritima Bauh.) in the pre-Linnaean period (generally not recognized by today's science).  I would be interested in any information about this etymology.

Perhaps one of the most common silver foliage plants you'll see these days, offered by growers around the world and used in a variety of climates as an 'annual' bedding plant.  In mediterranean climates, this is best considered a short-lived, shrubby perennial.  If you are keen to keep the foliar effect as long as possible, it is best to remove flower stems as they form — these can often spoil the look of leaves and make the plant floppy and untidy.  When grown dry and more natural, the form is more compact and the aging flowers are possibly in keeping with a less formal theme.

Massive amounts of Jacobaea maritima are produced for the horticulture trade each year.

A dizzying array of cultivars exist and 'new' forms are always being introduced by growers and seed houses.  Most are fairly similar though you might find one does better for you in your particular area.  Finely dissected, narrow, feathery lobes seem to be what breeders feel is most desireable: 'New Look', 'Silver Lace', 'Silverdust', 'Snowstorm', 'White Diamond'.  Growers may also offer cultivars under erroneous names.

There is popular interest in using this plant for container arrangements, so dwarf forms seem to be a trend - 'Alice', 'Silver Dust', 'Silver Queen' — though there is a lot of conflicting data about cultivar size, perhaps because of the variety of climates and conditions (e.g. pot culture) in which the plant is grown.  Because this species tends to be perennial in mediterranean climates (in colder climates it sometimes does not survive the cold), the ultimate height & width will likely be more than advertised.  Because of the ease in which this species is propagated, a desirable plant may be obtained and/or maintained in this manner.  Personally, I enjoy a particular form of unknown origin I found self-seeded in a local garden - its large leaves are held in an interesting manner quite unlike the standard offerings in the nursery trade (more 3-dimensional, not not at all flat).  This form seems closer to wild growing forms I've seen in photos of the Mediterranean.

The interesting cultivar usually called 'Cirrus' has leaves that are mostly entire, with large rounded tips and occasional lobing closer to the petiole.  This plant can be (or seems) larger in proportion to other cultivars — the white of its leaves is certainly very striking because of the solid surface.  this form has recently become very popular with floral arrangers, who find the grey fuzzy leaves well suited to their modern color schemes and designs.

Seán A. O'Hara

References

William T Stearn. 2004. Botanical Latin. Timber Press. ISBN 0881926272 / ISBN13 9780881926279 http://gimcw.org/books/bookinfo.cfm?bookid=blwts 

Germplasm Resources Information Network (GRIN). National Plant Germplasm System. USDA Agricultural Research Service. Website http://www.ars-grin.gov/npgs/aboutgrin.html 

Caroli Linnæi (Carl von Linné). 1753. Species plantarum. Laurentii Salvii (Lars Salvius). http://gimcw.org/books/bookinfo.cfm?bookid=spcl 

Lorenzo Peruzzi, Nicodemo G. Passalacqua, & Charlie E. Jarvis. November 2006. Typification of the accepted names in the Jacobaea maritima group (Asteraceae). Taxon. 55(4): pp. 1001-1004. International Association for Plant Taxonomy (IAPT). http://www.jstor.org/stable/25065696 

P.B.Pelser, J.-F.Veldkamp, & R. van der Meijden. 20 February 2006. New Combinations in Jacobaea Mill. (Asteraceae - Senecioneae). Compostiae Newsletter. 44: pp. 1-11. The Swedish Museum of Natural History. http://www.biodiversitylibrary.org/pdf3/003693100048846.pdf