In DeliSoil, Living Labs are being used as networks for experimental co-development and have proved to be a key approach for implementing the European Union’s Soil Mission. In the Satakunta region in Finland, a DeliSoil Living Lab network operates across municipalities Säkylä, Eura and Huittinen and area nearby. Within this Living Lab area, side streams from the local food industry are being researched, developed, and tested for use as recycled nutrient materials. Over the past two years, a field trial which is conducted by the Pyhäjärvi Institute, the Natural Resources Institute Finland (Luke) and Apetit’s Räpi experimental farm has evaluated several materials as fertilisers:

• Apetit’s compost
• Digestate from a biogas plant (derived from food industry side streams)
• Hydrochar (HTC-char) produced from carrot processing residues via hydrothermal treatment
• Biogas digestate both with and without the addition of biochar.

Additionally, commercially available organic and mineral fertilisers were used as benchmarks. Spring wheat was grown in the trial field during the first summer in 2025, followed by beetroot in the second year in 2026.

During the first growing season, there were virtually no observable differences in the crops across the experimental plots. However, protein analyses of the harvest, as well as nutrient, pH, and microbial analyses of the field soil, may reveal differences between the various materials applied. Measurements continued into the second growing season without any additional application of recycled nutrients. The experiment aimed, among other things, to determine the duration of the fertilising effect of different products within the soil. Another objective was to assess the impact of recycled materials on soil nutrient status, carbon storage, and microbial biomass, as part of an evaluation of soil health.

Experiences from field trials on private farms

In addition to the trials conducted at Apetit’s Räpi experimental farm, recycled fertilisers were also tested on fields across three private farms. During the first growing season, two farms cultivated oats, while the third grew spring wheat. Soil samples were collected from the pilot fields and analysed in spring 2025, while crop nitrogen content was monitored throughout the growing season.

During the second growing season, the trials continued with winter wheat, sugar beet and oats. The participating farmers showed great interest in the trials and were actively involved in their implementation. Crops and individual fields were carefully selected to ensure that testing recycled fertilisers, including any uncertainties associated with their use, would not compromise crop production or the subsequent use of the harvested crops.

Räpi experimental farm’s Field Day

The annual Field Day at Apetit’s Räpi experimental farm takes place around the turn of July and August. Over the past two years, the event has also provided an opportunity to showcase the DeliSoil project and activities carried out within the Living Lab area.

The Field Day attracted 65 participants in 2025 and approximately 40 in 2026. In 2025, participants had the opportunity to visit the DeliSoil field trial and learn about the ongoing research directly in the field. The following year, the focus shifted to presenting and discussing the results of the first growing season.

Alongside the DeliSoil activities, the programme covered a wide range of agricultural research and practical topics. These included potato research, with a focus on late blight, fertilisers and varieties, as well as trials on legumes, carrot varieties and pest management. Participants also learned about innovations in crop protection, such as the use of biological mulches to supress weed growth.