Xeronema callistemon

Xeronema callistemon is a species of flowering plant endemic to the Poor Knights Islands and Taranga Island in the north of New Zealand.[1] It was discovered in 1924 and has a common name Poor Knights lily. The plant is listed as vulnerable in the 1997 IUCN Red List of Plants,[2] but as of October 2010 is not listed in the IUCN Red List of Threatened Species.[3]

Xeronema callistemon
Xeronema MRD Otari.jpg
Poor Knights lily, Otari-Wilton's Bush, Wellington, New Zealand
Scientific classification edit
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Order: Asparagales
Family: Xeronemataceae
Genus: Xeronema
X. callistemon
Binomial name
Xeronema callistemon
W.R.B. Oliv


The common name of the plant originates from the Poor Knights Islands on which it was discovered. The islands, in turn, were so named because of their similarity in shape to the Poor Knights Pudding – a bread-based dish popular at the time of their discovery by Europeans.[4]

The botanical species name means "with a beautiful stamen", referring to the prominent red stamens of the plant's flowers.[5]


The green stalks of Xeronema callistemon start growing vertically, initially sheathed by overlapping leaves. As the flower emerges, the stalk then turn sideways, growing a red flower raceme with prominent red stamens tipped with orange pollen and resembles a giant bottlebrush[6] or toothbrush.[7] The individual flower tepals are 10–15 mm long, the stamens up to 4 centimetres (1.6 in) tall, and the length of the brush is usually between 18 and 25 cm (7.1 and 9.8 in) and can reach 45 cm (18 in). The plant itself is about 1 m (3.3 ft) tall and 1–4 m (3.3–13.1 ft) wide.[1][8]


Xeronema callistemon growing on one of the Poor Knights Islands

Xeronema callistemon usually grows on rhyolite sea cliffs and rocky outcrops and sometimes in forest. It requires much water and is pollinated by birds and butterflies.[9] If its seed falls on a nearby tree, such as Metrosideros excelsa, then it may grow as an epiphyte on it. The species has no obvious natural enemies and is listed as vulnerable because it grows naturally only on two islands. These islands are protected by the New Zealand Government as nature reserves and have a limited access. However, the plant is becoming popular for cultivation in private gardens.[7] A related species, Xeronema moorei, is found on the islands of New Caledonia, 1500 km to the northwest.[1][10]


Plants grow from fresh falling seeds. Although they germinate easily, it might take 10–15 years for them to grow into the flowering size. They flower between September and December, peaking in October (spring in New Zealand).[1]


  1. ^ a b c d Xeronema callistemon f. callistemon, Xeronema callistemon f. bracteosa
  2. ^ 1997 IUCN red list of threatened plants, ISBN 2-8317-0328-X p.746
  3. ^ http://www.iucnredlist.org/ Archived June 27, 2014, at the Wayback Machine and search for Xeronema callistemon
  4. ^ James Cook, John Beaglehole, Philip Edwards The journals of Captain Cook, Penguin Classics, 1999 ISBN 0-14-043647-2, p. 93
  5. ^ "Xeronema callistemon - New Zealand Plant Conservation Network". Retrieved 12 October 2018.
  6. ^ Horticultural use of native plants. Specialist plants, Ministry for Culture and Heritage of New Zealand
  7. ^ a b Barbara Matthews Growing Native Plants, Taylor & Francis, 1979, ISBN 0-589-01274-6 p. 50
  8. ^ Journey to the Poor Knights Islands
  9. ^ Mark W. Chase; Paula J. Rudall; Michael F. Fay & Kate L. Stobart (2000). "Xeronemataceae, a New Family of Asparagoid Lilies from New Caledonia and New Zealand". Kew Bulletin. 55 (4): 865–870. doi:10.2307/4113631. JSTOR 4113631.
  10. ^ Jan 16, 2006: Xeronema callistemon