Danish: pibeløg, Finnish: pillisipuli, Icelandic: pipulaukur, Norwegian: pipeløk, Swedish: piplök. Text by Kristina Bjureke. Photos by Kristina Bjureke and NordGen.

The Welsh onion is a perennial plant with inflated leaves as long as the stem. The flowers are white and occur in dense, round heads. The species was introduced to Europe from East Asia but is no longer known in the wild in Asia. Welsh onions have been established in Norwegian nature long before the year 1800 and are classified in the Norwegian red list (2021) as highly threatened (EN).

The Welsh onions in Gudbrandsdalen in Norway are not as tall as more modern cultivated varieties. The species was formerly planted on turf roofs and used as a vegetable and spice plant. It is not known how old this custom is and there are several potential explanations for the tradition. It may be because it could not be reached by grazing animals. In addition, it probably served as protection against the dry vegetation on the peat roof catching fire. Other plants used for this purpose are the common houseleek (Sempervivum tectorum) and roseroot (Rhodiola rosea). There may have been both practical and magical motives behind the cultivation on the turf roofs. The low-growing form of Welsh onion and the custom of using it on turf roofs is not known from the other Nordic countries.

Rare Plant Preserved on Roofs

In Norway, Welsh onion is rare, and their distribution is fragmented and limited to a small area. Larsen (2016) reports that of the now known 49 populations of Welsh onion, 23 are intact, 2 partially intact, 21 extinct, 2 likely to be extinct, and one population of uncertain status. Larsen (2016) estimates a decline in the number of localities of 28% during the last 30 years and many old houses with turf roofs have disappeared. Some recent activities on cultural history conservation are working to preserve the old Welsh onions on peat roofs and some have planted them on new roofs.

In Sweden, Welsh onions are considered to have been actively introduced after 1800 and therefore end up in the “Not Applicable” (NA) category in the national red list.

While here in Europe we use Welsh onions as a food and spice, in China and Japan it has also been used as a medicinal plant. In these countries Welsh onions are still widely grown. Welsh onions are included in the living collection of botanical gardens in Norway with the aim to improve their conservation.

References

Larsen, B.H. (2016). Pipeløk Allium fistulosum i Oppland – status og forvaltning i 2016. Miljøfaglig Utredning Rapport 2017-30 76.

Solstad H, Elven R, Arnesen G, Eidesen PB, Gaarder G, Hegre H, Høitomt T, Mjelde M og Pedersen O (24.11.2021). Karplanter: Vurdering av pipeløk Allium fistulosum for Norge. Rødlista for arter 2021. Artsdatabanken.