Emerging flower buds of Ajania pacifica. Photo by Cosima Wolter .

A. pacifica foliage - perhaps the main reason it is sought by gardeners.

The raylessrayless flowers of A. pacifica. Photo from 四季の花 (Flowers of the Season) .

Compare this plant to:

Brachyglottis hybrids

Salvia discolor

mouse-over for info height : 8-24in • 20-60cm width : 24-32in • 60-80cm USDA : 5-9  Sunset : 1-24  AU : 1

Ajania pacifica (Nakai) K.Bremer & Humphries 1993

 eye-YAN-ee-uh   puh-SIH-fih-kuh

Asteraceæ • Asteroideæ • Anthemideæ • Artemisiinæ

Has also been placed in Compositæ

Ajania : after the russian port city Ayan (Sea of Okhotsk) • pacifica : of the Pacific

gold and silver chrysanthemum, beach chrysanthemum • Française: chrysanthème du Pacific, chrysanthème mimosa • Italiano: crisantemo del Pacifico, mimosa d'oro • Português: crisântemo-prateado • Russian: аяния тихоокеаническая • Japanese: iso-giku イソギク

עברית (Hebrew): חרצית פסיפית, אג'ניה פסיפית

Endemic to Japan's coast from Inubo Point on the Boso Peninsula down to Omae Head in Shizuoka, and around the coasts of the Izu Oshima islands.

This perennial prized for its attractive, white or 'silver' edged foliage resulting from the extension of white tomentose leaf undersides.  The lobed shape of the leaves remind one of chrysanthemums (Dendranthema ×grandiflorum), showing the close relationship to this genus.  It typically forms a dense foliage mound to 8-24in · 20-60cm tall that spreads over time by rhizomes to as much as 24-32in · 60-80cm wide.

Autumn bloom (long night photoperiodic like their cousins, the Chrysanthemums) features numerous small, button-like, yellow, rayless flowers borne in densely-packed corymbs late in the season (or not at all in short season, cold winter climates).  These flower clusters are relatively long-lasting and have become favored by floral arrangers.

Requiring well drained soils, it is somewhat drought tolerant when established, but prefers preiodic water during dry months.  Often growing in very sandy soils, it is probably best to keep the crown of the plant 'high and dry' while the root extremities should probably not be allowed to dry out completely.  Part of the Siberian/Japanese coastal flora and therefore prefering cooler temperatures (provide some afternoon shade in hotter regions).

Because of the beauty of this plant, and because it prefers (even requires) good drainage, is it sometimes found in mediterranean climate gardens.  It is quite hardy in cold climates, going completely dormant in cold-winter regions, but in warmer climes it is more-or-less evergreen (though at its best in spring and summer).  To maintain the handsome foliage for which this plant is noted, periodically trim close those stems that are finished flowering or too old, encouraging fresh replacements.  To keep the foliage unblemished, protect from mollusks (slugs and snails).

Prohibited in some areas because it is a host to white rust.

Ajania 'Pink Ice', a hybrid of A. pacifica and Dendranthema ×grandiflorum  with short, pale pink ray flowers.

Hybrids have recently become available and are even starting to replace this species in cultivation.  This development is driven by the desire to combine the striking leaves of this species with the more typical composite flowers (with rays) of hybrid chrysanthemums (Dendranthema ×grandiflorum).  Because these hybrids are generally listed as A. pacifica cultivars, or sometimes even without the cultivar names, it is becoming harder to obtain the true species from unqualified plant lists.

For more information about this breeding program, which includes challenges regarding the differing chromosone numbers for A. pacifica (2n=90) and Dendranthema ×grandiflorum (2n=54), see the following article (in Japanese):

イソギク(Ajania pacifica)の利用によるキクの新しい生殖質の作製 

(Creating Novel Germplasms of Chrysanthemum by Employing the Ajania pacifica).

There are forms of this hybrid in white (matches the white tomentum), yellow (why would you bother?), and pink (usually very pale to 'dirty').  Growers like them because of the their compact size, quick growth, and multitude of flowers, making a cute 'impulse purchase' pot plant.  Clearly novelty is attractive to many but this author does not feel these hybrids are an improvement over the grace and character of the original species.

Seán A. O'Hara

What others have to say

Do you have something to say? We'd love to hear from you.

Olivier Filippi - Meze, southern France

The Dry Gardening Handbook: Plants and Practices for a Changing Climate

This perennial has been happy for several years in one of the least hospitable area of our garden.  The plan spreads slowly by stolons to form a pretty, regular-shaped cushion.  It's semi-evergreen velvety grey leaves have a narrow silver border.  The fairly discreet yellow flowers open into a profusion of little cushions in October to November, a season when most flowering the garden is over.  Ajania pacifica tolerates alkaline conditions well.  It is a plant that is easy to grow, undemanding as to soil type and long-lived.  As the stems have a woody base that is bare in winter, they can be cut to the ground in February or thereabouts to encourage new growth, so you can enjoy the elegance of the fresh foliage in spring.  Propagation is by division in autumn or by softwood cuttings in spring.

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 

Dr. Giuseppe Mazza; text by Pietro Puccio; translation by Mario Beltramini. Ajania pacifica. PhotoMazza. Website http://www.photomazza.com/?Ajania-pacifica  [accessed 15 January, 2013].

Olivier Filippi. 2008. The Dry Gardening Handbook. Thames & Hudson. ISBN 0500514078 / ISBN13 9780500514070 http://gimcw.org/books/bookinfo.cfm?bookid=tdghof