1. Family: Aristolochiaceae Juss.
    1. Genus: Asarum L.
      1. Asarum asaroides (C.Morren & Decne.) Makino

        Asarum is a genus (a group of related species) of perennials with underground stems (rhizomes). It occurs across the temperate regions of the northern hemisphere, with the highest concentration of species in China and Japan. Their usually evergreen, long-stemmed leaves can be attractively patterned and the curious, sometimes sinister-looking flowers appear from beneath them, borne on short stalks. The flowers are commonly in shades of dull purple, brown or green.

    [KSP]

    Kew Species Profiles

    General Description
    Asarum asaroides was introduced to Europe by the German, Philipp von Siebold, on his return from Japan in 1830.

    Asarum is a genus (a group of related species) of perennials with underground stems (rhizomes). It occurs across the temperate regions of the northern hemisphere, with the highest concentration of species in China and Japan. Their usually evergreen, long-stemmed leaves can be attractively patterned and the curious, sometimes sinister-looking flowers appear from beneath them, borne on short stalks. The flowers are commonly in shades of dull purple, brown or green.

    Taken in its broadest sense, the genus Asarum (wild ginger) contains around 100 species, but in the past it has been split into several smaller genera, separated by minor differences in the flowers. The genus Heterotropa was established by the Belgian botanists Charles Morren and Joseph Decaisne in 1834, and they described one species, H. asaroides, based on the plant incorrectly named Asarum virginicum in Carl Peter Thunberg's Flora Japonica (1784). It was renamed Asarum asaroides by Tomitaro Makino in 1910.

    Species Profile

    Geography and distribution

    Around 50 species of Asarumgrow in Japan and the Ryukyu Islands, many of them found only there. They include A. asaroides, which occurs in south-west Honshu and Kyushu.

    Description

    Leaves: The spotted and mottled leaves are broadly ovate (egg-shaped) to roughly triangular in outline and up to 12 cm long. They persist throughout much of the year but the main growing period is during spring and summer.

    Flowers: The dull, dark purplish-green flowers appear in early spring, and have a pear-shaped tube 2–2.5 cm long, and three spreading, rounded to triangular lobes. Around the mouth of the tube, the perianth (sepals and petals) lobes are wrinkled, these ridges being lighter purple or crested with white. The flowers have also been described as 'perfumed somewhat like a ripe apple’ and ‘large as a walnut’.

    Uses

    Asarums have been cultivated in Japan for hundreds of years. Some believe they offer protection from earthquakes and storms if planted at the front of houses or hung from the eaves.

    Cultivation

    Although Asarum asaroides can tolerate a few degrees of frost, it is best grown in a cold frame to keep off rain in the winter and provide some protection during particularly cold spells. Use an acidic, humus-rich, free-draining soil mix and place the rhizomes just below soil level. During the winter keep the soil just moist but once growth begins in spring, increase watering and never let the soil dry out throughout spring and summer. If this species is tried in the open garden, plant it in a cool, shady, sheltered spot.

    This is a slow-growing plant but older clumps can be carefully divided in spring, by cutting off portions of the rhizome with roots and a growing point. If seed is produced it should be collected and sown immediately, before it dries out. Germination will usually occur in early spring but may take over a year.

    This species at Kew

    Asarum asaroidescan be seen in the Davies Alpine House at Kew when in flower.

    Spirit-preserved of Asarum asaroides are held in Kew’s Herbarium, where they are available to researchers, by appointment. The details of one of these can be seen online in the Herbarium Catalogue.

    Distribution
    Japan
    Ecology
    Woodlands; often growing in deep shade, in valleys or ravines and on north-facing hillsides.
    Conservation
    Not evaluated according to IUCN Red List criteria.
    Hazards

    None known.

    Images

    Distribution

    Asarum asaroides (C.Morren & Decne.) Makino appears in other Kew resources:

    Date Identified Reference Herbarium Specimen Type Status
    48462.000

    First published in Bot. Mag. (Tokyo) 24: 297 (1910)

    Accepted in:

    • [4] Govaerts, R. (1995) World Checklist of Seed Plants 1(1, 2): 1-483, 529. MIM, Deurne.

    Literature

    • [1] Beentje, H. (2010). The Kew Plant Glossary. Royal Botanic Gardens, Kew.
    • [2] Image: Kindly donated by Takato Natsui: The Plant List (2010). Asarum asaroides.
    • [3] Wilford, R. (2010). Alpines from Mountain to Garden. Royal Botanic Gardens, Kew.
    • [5] Boyce, P. (1994). Two Asian Asarum species. Curtis’s Bot. Mag. 11: 59-65
    • [6] Graham, R. (1840). Heterotropha asaroides. Curtis’s Bot. Mag. 66: t.3746.

    Sources

    International Plant Names Index
    The International Plant Names Index (2016). Published on the Internet http://www.ipni.org
    [A] © Copyright 2016 International Plant Names Index. https://creativecommons.org/licenses/by/3.0

    Kew Species Profiles
    Kew Species Profiles
    [B] http://creativecommons.org/licenses/by-nc-sa/3.0
    [C]

    World Checklist of Selected Plant Families
    World Checklist of Selected Plant Families(2016). Published on the Internet http://apps.kew.org/wcsp/
    [D] See http://kew.org/about-kew/website-information/legal-notices/index.htm You may use data on these Terms and Conditions and on further condition that: The data is not used for commercial purposes; You may copy and retain data solely for scholarly, educational or research purposes; You may not publish our data, except for small extracts provided for illustrative purposes and duly acknowledged; You acknowledge the source of the data by the words "With the permission of the Trustees of the Royal Botanic Gardens, Kew" in a position which is reasonably prominent in view of your use of the data; Any other use of data or any other content from this website may only be made with our prior written agreement. http://creativecommons.org/licenses/by-nc-sa/3.0
    [E] © Copyright 2016 International Plant Names Index and World Checkist of Selected Plant Families. https://creativecommons.org/licenses/by/3.0