Recyclable polymer foams as synthetic soils for cultivation of high­-value horticultural crops

Grantham Scholar Harry Wright is now a research associate at the University of Sheffield, working on disease resistance of tomato crops in hydroponic systems using soil microbes. At the Grantham Centre Harry researched how to optimise PUF to mimic natural soil. 

Harry Wright’s project at the Grantham Centre

In order to increase yields, more and more farming is done in controlled environments e.g. greenhouses. Additionally controlled environments allow farming in areas not normally suitable for agriculture. However, these farming methods often suffer from soil borne diseases and pests. In turn this leads to the use of environmentally damaging chemical control. As a result there is increasing interest in alternative, soilless growing mediums.

Because polyurethane foams (PUF) allow roots to grow through the spaces in foam, it has promise as a synthetic soil. However, many aspects of these foams need to be optimised before a viable product can be produced. As such, this project will look at optimising the formulation of PUF, in order to have it closely mimic natural soil. This will include the use of bio-based raw materials, the addition of natural fillers to act as slow nutrient release agents as well as the addition of beneficial microbial life.

Finally, this project will seek to close the loop and ensure that the PUF is recyclable in a manner whereby the foam breaks down into reusable materials.


Harry wrote about reusing old mattresses to grow food at the Za’atari refugee camp. Read: Seeds Without Soil: A New Use For Old Beds.

And you can read all about the Grantham Centre’s work at Za’atari refugee camp.

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A close up on Tony Ryan at work in his lab

Professor Tony Ryan OBE

Grantham Centre Co-Director


Professor Duncan Cameron

Director of Institute for Sustainable Food