Japanese knotweed as a circular raw material for mushrooms

Germination and its partners are developing circular mushroom self-grow kits.

Japanese knotweed is proliferating in Flemish roadsides, gardens and natural areas. This is a problem because the invasive plant species takes over biodiversity in many areas and its strong roots cause damage to (water) road infrastructure. On top of that, controlling the plant is an expensive job for municipalities and site managers.

Kiemkracht therefore came up with a solution that is efficient, affordable and above all circular. Together with its partners, a control offer was developed in the form of a multi-year control contract. Under the guise of 'better prevention than cure', the choice is made to control Japanese knotweed early in order to avoid greater damage and thus also major costs.

To make the project circular, work is being done with the plant residues left over after 'harvesting' Japanese knotweed. To this end, Kiemkracht, Mycelia and Urban Farmer joined forces. Together, they developed mushroom self-grow kits. At first sight, this does not seem innovative, as such kits have been around for a while, but ever since the first grow kits were developed in the 1970s, the same problem kept cropping up: shelf life. The limited shelf life of the kits, coupled with their sensitivity to high temperatures, meant that many unsold kits remained in garden centres and producers, often resulting in unsellable products, flies and stench.

A new concept was developed by the trio. Instead of selling ready-made tar kits, only the non-perishable, dry raw materials are sold. Once the user is ready to use their kit, the accompanying spawn can be 'claimed' by ordering it. This is then delivered fresh within 2 days. Urban Farmer already marketed this system in the United Kingdom where the products are already widely sold and customer satisfaction is as high as 97%!

The new approach brings many benefits. Garden centres can store the kits for longer and do not need refrigeration for this. Distributors can always deliver fresh and therefore no longer have dissatisfied customers and the customers themselves can count on good and stable results. Even better, biodiversity can be revived in various places in Flanders and infrastructure is no longer affected by the invasive plant.


Partners Regionaal landschap Schelde – Durme, Urban farmer, Mycelia