Residual wool from Norwegian sheep replaces plastic pots in Norwegian nurseries

1000-2000 tonnes of wool go to waste

Every year, approximately 4000 tonnes of wool from Norwegian sheep and lambs are classified, but only just over half is utilized. Norwegian sheep and lambs produce around 4000 tonnes of wool annually, yet just over half is put to use. We have strict rules on wool sorting in Norway, and it is categorized into two classes. Anything not classified as first-class wool ends up in a common category; downgraded wool. This is wool that, for various reasons, cannot be used for materials such as knitting yarn and upholstery fabric, nor for ready-made clothing. Currently, there are few applications for the downgraded wool, which results in most of it going to waste. This constitutes 1000-2000 tonnes of wool annually. Additionally, large amounts of wool are thrown away or burned on sheep farms without ever making it to the wool reception facilities, as farmers lack financial incentives to deliver wool considered to have low quality. However, not all downgraded wool is worthless. The Woolly Pot project aims to contribute to research on what the downgraded wool can be used for, so that more of the wool produced can be utilized.

Soft wool for sturdy pots

In the spring of 2022, test production of the wool pots began. Toppe Gartneri conducted tests for large-scale plant production, and Bybonden in Bergen for private individuals. The goal is for the wool pots to be available for everyone, so that those of us who buy plants in stores can take them home in environmentally friendly wool pots.

There are several tasks that need to be addressed for the wool pots to be ready for the market. Since the wool is naturally soft, the main challenge is to find the right organic binders to stiffen the wool so that it can hold soil and plants. The binders used also affect how long it takes for the wool to break down in the soil. At NORSØK, the decomposition time of the pots has been tested in experimental fields. Through the project, the team has observed that it is possible to use different binders to make pots with varying decomposition times. Thus, some can break down quickly, while others retain their shape for a long time and can be reused, all depending on what the customer needs.

Another challenge they have encountered is that it has been difficult for the automated machines used in the industry to handle the pots. Wool pots will always have some natural irregularities, which makes them not as straightforward to mass-produce compared to the smooth plastic pot. Woolly Pot is therefore being developed in close collaboration with Toppe Gartneri, which is testing the scaling of production. In this phase, any issues will be detected so that the pots can be improved along the way and adapted to the machines in production. In addition to testing different binders to stiffen the wool, they are also testing how well the pot holds up against water and in various temperatures.

Win-Win-Win

Using wool instead of plastic offers several benefits, both economic and environmental. Wool breaks down in the soil, meaning there is no need to recycle the material as is necessary with plastic. Thus, less plastic is needed in general, in addition to saving the money required for handling plastic. For plant production, wool pots also yield highly positive effects since wool contains several nutrients such as nitrogen, potassium, and sulfur, which the soil and plants need. Therefore, the plants can receive nutrients directly from the pot, and growers can reduce the use of fertilizers. This leads to lower costs and a reduced environmental footprint. The results of the investigations will provide new knowledge, which can promote the use of natural, environmentally friendly alternatives to fossil materials.

Woolly Pot is developed by Bioregion Institute in collaboration with Toppe Gartneri, NORSØK, Bybonden and Sjølingstad Uldvarefabrik.