Arctic nettle, from weed to money

Abstract

Nettle has gained a lot of interest recently and its cultivation is starting industrially in other European countries. Few companies in Lapland and other parts of Finland are presently using nettle in their products but they are facing issues in raw material supply, especially organic raw-material. The objective of ARKNOKK was to establish the basis for a nettle value chain in Lapland. Nettle grows rapidly and cultivation techniques are known. Although its establishment may be challenging, a nettle field can be productive for 10 years. In ARKNOKK, raw-material yields were optimized using organic cultivation methods. In addition to the common stinging nettle (Urtica dioica ssp dioica, “etelännokkonen”), we took advantage of a northern subspecies (U. dioica ssp. Sondenii, “pohjannokkonen”) which is rare, has few horns but can be cultivated as well. Several companies interested in nettle raw material were partners of ARKNOKK. One valuable application of nettle in Lapland that was tested in the project was winter supplementary feeding of reindeer. The main results of ARKNOKK were: - Nettle thrives well in conditions of Northern Finland and satisfying yields were obtained (4.6 ± 2.7 t DW/ha shoots) with up to 4 harvests/season. The best planting system in our conditions in Lappia, Loue was strawberry ridges, with plastic mulching for easier weed control. - Bioactive composition did not significantly vary among nettles from 12 different Finnish origins. Best accessions of ssp dioica and ssp Sondenii were selected. Accessions are also conserved as in vitro cultures and seeds produced from selected parents have been produced. - Nettle-supplemented winter feed brings benefits to reindeer well-being but at present, the higher cost of nettle-supplemented feed would restrict its use to reindeers involved in racing, or tourism activities.

Several challenges for the establishment of a nettle value chain were identified: - A controlled seed availability is lacking. - Field establishment using direct seeding is unsuccessful. Seedlings planting is effective but expensive and commercial production of seedlings is lacking. - Nettle leaves need to be processed rapidly after harvest and the access to post-harvest processing facilities is challenging, especially in remote areas. - The price competition with non-Finnish nettle is strong. - The Finnish production presently relies on too few producers. - The nettle-based products are limited, and the market still immature. Further research is necessary to address those challenges. Nettle represents an interesting alternative crop, especially in Northern Finland where the choice of cultivable crops is limited due to harsh environmental conditions. Nettle is a perennial, endogenous plant, with low input requirements. Although it has many application potentials, building a reliable and profitable nettle value chain is now challenging due to the lack of several actors, especially at the level of post-harvest processing and product development.