Dr Raghavendra Prasad

Raghavendra leads our Transition to Peat-Free project. This interdisciplinary research project investigates sustainable peat alternatives to accelerate the horticultural industry’s transition to peat-free growing media

What do you do?

During the DEFRA and industry collaborative Transition to Peat-Free project, I am investigating various responsibly sourced, locally available, economically viable and ecologically sustainable peat alternatives. I am currently working alongside eight leading UK growers (Allensmore, The Farplants Group, Hillier, Hills Plants, Johnsons Nurseries, Lovania, Vitacress and Volmary), who collectively produce around 143 million plants every year, as well as several growing media manufacturers.

In this five-year collaborative project, my work with the RHS convenes government, growers and growing media manufacturers, through the Growing Media Association and key horticultural stakeholders, to research sustainable alternatives to peat in large-scale commercial settings. Progress and research findings are shared with growers and industry through industry events. The 2023 RHS Industrial Transition to Peat-Free Survey provided a benchmark for the project through documenting the peat-free status of the UK horticultural industry in 2023.

Key areas of focus include:

  • Peat-free production of plants and plug plants
  • New growing media technologies to replace the estimated 1.7m m3 of peat used by the UK horticultural industry in 2021
  • Growing protocols
  • Best practice use of the latest products
  • Developing peat-free solutions for challenging plant groups such as ericaceous and carnivorous species
I believe that many organic by-products from agricultural and horticultural processes, which are currently considered waste, should instead be regarded as ‘out-of-place’ resources that have potential to replace peat.

“I’m highly motivated and excited to work alongside key stakeholders in the UK horticultural industry to address some of the challenges associated with peat-free growing, in order to accelerate the industry’s transition to peat-free.”

Why is your team’s research important?

Peat and climate change

Peatlands play a tremendous role in supporting unique biodiversity, mitigating floods, maintaining clean water bodies and crucially, capturing nearly 30% of the world’s terrestrial carbon. UK peat bogs alone are capable of capturing nearly 3 billion tonnes of carbon.

Peat extraction for horticultural use removes this stable, sequestered carbon and releases it into the active carbon cycle, exacerbating climate change. This means the ability to keep peat bogs intact, and to use other organic materials (especially 'waste' materials) as peat alternatives, will have great significance in combating climate change.

RHS commitment to be peat-free by 2025

Our project will contribute towards delivering the RHS peat-free pledge. This forms part of the RHS Sustainability Strategy, which aims for net climate positivity by 2030.

To ease the transition to peat-free growing

Throughout the project, our evidence-based results will be shared with the wider horticultural industry, including specialist nurseries. They will also be shared with the UK’s 30 million home and community gardeners who, armed with a better understanding of sustainable alternatives and best practice advice, can aid the transition to peat-free.

We believe that bringing the industry together to address key scientific and technical challenges will strengthen relationships between growers, gardens and researchers; build confidence; and allow new horizons to be reached.

Projects I’m working on now

Completed projects

  • The spent mushroom substrate as a growing medium for strawberry (Fragaria × ananassa Duch.) (2017-2021)
  • Agro-technique intervention for strawberry (Fragaria × ananassa Duch.) on vertical growing system under naturally ventilated greenhouse (2015-2017)


  • Studied and trained in three different countries, collaborating and working with interdisciplinary researchers across agronomy, horticulture, plant physiology and remote sensing
  • Attended ‘Sustainable Agricultural Solutions’, a cutting-edge knowledge and technology programme at the Ben-Gurion University of Negev, Israel
  • Hosted a discussion table during the Bioeconomy Working Group’s project facilitation workshop; a call for project proposals by the Circular Bio-based Europe Joint Undertaking (CBE JU)
  • Submitted project proposals to national and international funding bodies


  • Prasad R, Redmile-Gordon M, Gush MB and Griffiths A (2024, in press) Characterisation of peat-free growing media to facilitate the transition to peat-free horticulture. Acta Horticulturae (I International Symposium on Growing Media, Compost Utilization and Substrate Analysis for Soilless Cultivation)
  • Prasad R, Gush MB, Griffiths A and Thorpe C (2024) Transition to peat-free horticulture: the UK response. Abstract submitted to ISHS III International Symposium on Greener Cities: Improving Ecosystem Services in a Climate-Changing World (GreenCities 2024)
  • Gush MB, Blanuša T, Chalmin‐Pui LS, Griffiths A, Larsen EK, Prasad R, Redmile‐Gordon M and Sutcliffe C (2023) Environmental horticulture for domestic and community gardens – an integrated and applied research approach. Plants, People, Planet, 15 October 2023
  • Royal Horticultural Society (RHS) (2023) Industrial Transition to Peat-Free Survey: 2023
  • Prasad R, Lisiecka J and Kleiber T (2022) Morphological and yield parameters, dry matter distribution, nutrients uptake, and distribution in strawberry (Fragaria × ananassa Duch.) cv. ‘Elsanta’ as influenced by spent mushroom substrates and planting seasons. Agronomy, 12, p854
  • Prasad R, Lisiecka J, Antala M and Rastogi A (2021) Influence of different spent mushroom substrates on yield, morphological and photosynthetic parameters of strawberry (Fragaria × ananassa Duch.). Agronomy, 11, p2086
  • Jasinska A, Prasad R, Lisiecka J, Roszak M, Stoknes K, Mleczek M and Niedzielski P (2022) Combined dairy manure-food waste digestate as a medium for Pleurotus djamor—mineral composition in substrate and bioaccumulation of elements in fruiting bodies. Horticulturae, 8, p934
  • Lisiecka J, Prasad R and Jasinska A (2021) The utilisation of Pholiota nameko, Hypsizygus marmoreus, and Hericium erinaceus spent mushroom substrates in Pleurotus ostreatus cultivation. Horticulturae, 7, p396
  • Spiżewski T, Krzesiński W, Kałużewicz A, Prasad R and Zaworska A (2022) The effect of spent mushroom substrate enriched with selenium and zinc on the yield and photosynthetic parameters of lettuce (Lactuca sativa L.). Acta Scientiarum Polonorum Hortorum Cultus, 21, 3, pp83-97

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