This project advances sustainable growing media for soilless cultivation. Renewable organic fibres often exhibit limited stability, which can impact root conditions and the propagation of young plants. We will assess material stability, improve processing and amendments, test biodegradable binders for plugs, and refine fertilisation. Together with industry partners, we aim to ensure crop performance while reducing the sector’s environmental impact.

This project aims to increase the use of renewable plant fibres in growing media for propagation and potted
plants by improving the stability of these media.
The objectives of this project as below
• Develop reliable methods to assess the biostability of plant fibres (RQ1 & RQ2).
• Improve biostability of plant fibres through processing technologies (RQ3).
• Enhance the physical stability of propagation plugs using biodegradable binders (RQ4).
• Optimise fertilisation strategies for young plants and potted plants (RQ5)

The strategic advantages of targeting renewable plant fibres such as wood fibre, jute, flax, and miscanthus, are
such fibres are locally available in relatively high quantities, have low prices, have low water content
(storability) and can be transported when compressed (less logistics). Moreover, cultivation of those crops
provides ecosystem services (soil carbon storage, biodiversity and carbon dioxide mitigation). Disadvantages
are the low biological stability (i.e. high degradability) reflected in volume loss, poor water absorption, nitrogen
immobilization, etc., preventing growers from using more than 20-30% (by volume) of these materials in
growing media. Furthermore, biostability measurements obtained in laboratory tests do not always correlate
with material performance under real cultivation conditions.

D1. Factsheets summarizing lab methodologies for quantifying biostability and outlining
suitable processing path way for each group of raw materials.
D2. Description of the model predicting the release dynamics of slow-release nitrogen
fertilisers when incorporated with renewable plant fibres for propagation plugs.
D3. Description of the model to calculate base fertilisation requirements for fibre-based
blends for propagation substrates.
D4. Description of how biodegradable binders are incorporated with raw materials.
D5. Summary of growth trial outcomes and fertilisation advices.
D6. Description of the model predicting the release dynamics of slow-release nitrogen
fertilisers when incorporated with renewable plant fibres for potted plants.
D7. Description of the model to calculate base fertilisation requirements for fibre-based
blends for potted plants.
D8 Summary of growth trial outcomes and fertilisation advices.
D9. A final report consolidating the results from all work packages.