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

Grantham Scholar Dr Harry Wright is currently working on a £364k Knowledge Transfer Partnership with Vita Cellular Foams funded by InnovateUK on work directly leading from his PhD. The aim of the project is to recycle upholstery foam into a synthetic soil for non-food crops. Harry is also a part of an integrated programme of interdisciplinary research on ‘Healthy soil, Healthy food and Healthy people’ (H3). 

At H3, Harry works on developing novel polyurethane foams, which are optimised per crop, for use in hydroponic systems (growing without conventional soil). These have been shown to match or exceed growth of crops grown in alternative growing media (mineral wool). They are also looking at whether they can incorporate beneficial microbes into the foam to increase yield and suppress plant disease, making hydroponic plants more resilient to biotic stresses.

At the Grantham Centre Harry researched how to optimise polyurethane foams to mimic natural soil.

Outreach and awards

Harry won the University of Sheffield’s Open Research Prize 2023 in the individual staff category. He got the award for the development of FoamPi, an affordable open-source hardware solution to measure polyurethane foam reaction kinetics. Read more here!

Harry also 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.

Introduction to hydroponics with Dr Harry Wright. Watch Harry explain how hydroponics works and how to set up your own home system.

Social media

You can find Harry on Twitter and LinkedIn.

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.

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A close up on Tony Ryan at work in his lab

Professor Tony Ryan OBE

Grantham Centre Co-Director


Duncan Cameron

Professor Duncan Cameron

Chair in Environmental Sustainability