Aeonium arboreum

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Tree aeonium
Madeira, Palheiro Gardens - Aeonium arboreum (Marokko) IMG 2310.JPG
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Order: Saxifragales
Family: Crassulaceae
Genus: Aeonium
Species:
A. arboreum
Binomial name
Aeonium arboreum
Synonyms [1]
  • Aeonium doramaeWebb ex A.Berger nom. inval.
  • Aeonium doremaeWebb ex Christ
  • Aeonium holochrysumWebb & Berthel.
  • Aeonium manriqueorumBolle
  • Aeonium rubrolineatumSvent.
  • Aeonium vestitumSvent.
  • Sempervivum arboreum L.
  • Sempervivum urbicumLindl. nom. illeg.

Aeonium arboreum, the tree aeonium, [2] tree houseleek, or Irish rose,[ citation needed ] is a succulent, subtropical subshrub in the flowering plant family Crassulaceae.

Contents

Description

Aeonium arboreum in a bush setting. Aeonium arboreum - Jardin Botanico Canario Viera y Clavijo - Gran Canaria - 01.jpg
Aeonium arboreum in a bush setting.

Aeonium arboreum grows as a less branched subshrub and reaches stature heights of up to 2 metres. The more or less upright or ascending, smooth, not net-like patterned stem axes have a diameter of 1 to 3 centimetres.

Their leaves are in flattened rosettes with diameters of 10 to 25 centimetres at the end of the stem axes together. Young leaves are pressed tightly together. The obovate to oblate lanceolate leaf blade is pointed toward its apex and wedge-shaped at the base. It is 130 to 380 mm (5 to 15 in) long, 25 to 115 mm (1 to 4+12 in) wide and 1.5 to 3 millimetres thick. The green, usually purple-colored, glossy leaf surface is almost bare. The leaf margin is set with curved eyelashes.

The conical to ovate inflorescence has a length of 10 to 25 centimetres and a diameter of 10 to 15 centimetres. The inflorescence stem is 130 to 510 mm (5 to 20 in) long. The flowers sit on a 2-to-12-millimetre-long, slightly fluffy flower stem. Its sepals are also slightly fluff-haired with a pointed top and wedge-shaped base that is smooth and shiny green, red or purple. The yellow, narrow oblong to lanceolate, pointed petals are 5 to 7 millimetres long and 1.5 to 2 millimetres wide. The stamens are bare. It bears rosettes of leaves and large pyramidal panicles of bright yellow flowers in the spring. [3]

Distribution

The plant is endemic to the western Canary Islands of Tenerife, La Palma, El Hierro, La Gomera and Gran Canaria. The populations found on the Iberian Peninsula, the Moroccan coast and the Mediterranean are likely to be considered neophytes. [4] In colder temperate regions it needs to be grown under glass however in temperate regions with mild winters they are perennial.

Cultivation

Aeonium arboreum grows in sunny or slightly shaded places on weathered volcanic soil. [5] The purple cultivar 'Zwartkop' ('Schwartzkopf') has gained the Royal Horticultural Society's Award of Garden Merit. [6] A variegated form is grown as cultivar 'variegatum'.

Subspecies

Three subspecies are accepted. [7]

References

  1. The Plant List: A Working List of All Plant Species , retrieved 30 July 2016
  2. BSBI List 2007 (xls). Botanical Society of Britain and Ireland. Archived from the original (xls) on 2015-06-26. Retrieved 2014-10-17.
  3. Reto Nyffeler: Aeonium . In: Urs Eggli (ed.): Succulent Encyclopedia Volume 4 Crassulaceae (thick-leafed plants) . Eugen Ulmer Verlag, Stuttgart 2003, ISBN   3-8001-3998-7 , p 13.
  4. "International Crassulaceae Network: Aeonium arboreum". International Crassulaceae Network. Retrieved 19 February 2017.
  5. RHS A-Z encyclopedia of garden plants. United Kingdom: Dorling Kindersley. 2008. p. 1136. ISBN   978-1405332965.
  6. Aeonium 'Zwartkop' AGM. Archived 2014-03-28 at the Wayback Machine Royal Horticultural Society
  7. "Aeonium arboreum (L.) Webb & Berthel". Plants of the World Online . Royal Botanic Gardens, Kew . Retrieved 1 March 2025.
  8. "Aeonium arboreum subsp. korneliuslemsii (H.Y.Liu) Dobignard". Plants of the World Online . Royal Botanic Gardens, Kew . Retrieved 1 March 2025.