Halla Arboretum Glasshouses: Jeju Rare Plant House and Orchid House (한라수목원 온실)

The Halla Arboretum was planned on 14 January 1986 and opened on 20 December 1993, according to its official page and the Encyclopedia of Korean Culture. Its stated aim is to collect, propagate, conserve and display the genetic resources of Jeju's native flora. The Ministry of Environment designated it on 25 May 2000 as the country's second off-site conservation institution, and its Natural Ecology Experience Hall opened on 19 August 2005.

Greenhouses existed before 2014: a 2007 article already describes a greenhouse holding ferns and evergreen shrubs and an orchid room housed in a greenhouse of about 90 pyeong, with around sixty species. In September 2012 the Hallasan Research Institute announced a 2013-2017 specialisation programme that included remodelling the greenhouses and orchid rooms from 2014. On 23 September 2014 Jeju Province opened the Jeju Rare Plant House to the public as a glass greenhouse, at the end of a programme costing 410 million won, and had the building equipment and interior displays of the orchid house upgraded. A February 2021 article shows both halls in operation, with extended hours from March to November.

Both houses are glazed buildings: the 2014 press speaks of a "glass greenhouse", and a 2021 columnist describes the rare plant house as a glass greenhouse below the shrub garden, and the orchid house as a glass house reached by continuing along the path past the vine garden. The arboretum's official page lists two greenhouses totalling 837 m², 507 m² for the rare plant house and 330 m² for the orchid house.

Inside the rare plant house, the display is arranged in three themed spaces. One of them uses a scaled-down model of the island of Jeju, with plants grouped by zone from the coast to the mid-slopes. A small stream, a wall fountain and photo spots complete the layout, according to the 2014 article. In the orchid house, volcanic rocks from the island are set among the plants, according to the official page.

The rare plant house opened in 2014 with 996 plants in three themes: aquatic and wetland plants, rare and endemic plants, and plants of Jeju's lava forests (gotjawal), notably ferns. The list published on the official page, which does not strictly separate the themes, includes among others Ardisia crenata, the fern Mankyua chejuense (제주고사리삼), Paliurus ramosissimus, Psilotum nudum, Euchresta japonica, Ficus pumila, agaves, aloes, cacti and Bougainvillea glabra.

The orchid house holds the Jeju hallan (Cymbidium kanran), natural monument no. 191, together with Cymbidium goeringii (춘란), Dendrobium moniliforme (석곡), Neofinetia falcata (풍란), Aerides japonicum and others, thirteen taxa in all on the official list. A 2007 article counted around sixty species, some 350 pots and about 300 lava rocks. The arboretum as a whole presents 1,321 species (530 woody, 791 herbaceous) and more than 100,000 plants.

The arboretum lies in Yeon-dong, Jeju City, on the slope of the Gwangi cone (Sumokwon-gil). The route passes through the specialist gardens, twelve in number according to the official page; the rare plant house sits below the shrub garden and the orchid house further along the path, past the vine garden. The official page states that these halls may stay closed when management requires, and that they close on the days of Seollal and Chuseok.

The arboretum's monthly selection, quoted in 2007, places the hallan in November, a useful time for the orchid house. The visit combines naturally with the Natural Ecology Experience Hall, which presents the formation of the island and its volcanic rocks, and with the forest paths and the outdoor forest-bathing area, open all year.