Blenheim Estate has officially broken ground on a pioneering mushroom farm in Combe, Oxfordshire, marking a major step in its ambitious journey to become a net zero business by 2027.
Set within the estate grounds, the facility is the UK’s first fully circular gourmet mushroom farm. It will grow a variety of high-end mushrooms, including Oyster, King Oyster, Lion’s Mane, and Pink Oyster, using a unique substrate made entirely from Blenheim’s own organic waste: recycled coffee grounds, compostable packaging, sawdust, and other natural by-products from its cafes and estate operations.
A Circular Food Ecosystem in Action
The initiative is the latest milestone in the Country Estate Carbon Demonstrator Project, a collaboration between Blenheim Estate and environmental consultancy Tumblebug Ltd. The goal: transform estate-generated waste into a regenerative food and compost production cycle, while capturing carbon and reducing emissions.
The farm itself comprises three core units:
- A substrate preparation room, where organic materials are processed and inoculated with mushroom spawn.
- An incubation chamber, where mycelium colonises the substrate.
- A fruiting room, where the mushrooms are grown and harvested under carefully managed conditions.
The first harvest is expected in September, with mushrooms destined for Blenheim Palace kitchens, local markets, and more than 20 Oxfordshire venues. including Michelin-starred restaurants, that have already expressed interest in purchasing the estate-grown produce.
Waste to Table, and Back Again
What sets this farm apart is its commitment to full-circle sustainability. After harvesting, the spent mushroom substrate isn’t discarded. Instead, it undergoes pyrolysis (a high-heat process that breaks down organic waste in low-oxygen conditions) to create biochar, a carbon-rich, peat-free compost alternative.
This biochar is then used to grow new produce across the estate, especially in the Walled Garden, where the cycle of regeneration begins again.
Roy Cox, Managing Director – Estates at Blenheim Palace, commented:
“To become a net zero business by 2027 means we must look at every part of our operations and reduce our emissions, and we see this project as a major step towards achieving that, as well as creating circular businesses from our waste. It is vital that we work with partners like Tumblebug, and together we will find the best mix, or model, that is transferrable to other businesses who face similar challenges.”
A Model for Regenerative Farming
Tumblebug Ltd (named after the dung beetle, nature’s original recycler) is leading the technical vision. Their Ecobot machines process estate waste streams including coffee, card, food waste, sheep wool, and horticultural clippings. The farm also features a patent-pending pyrolysis unit, which supplies heat to the mushroom barns using energy generated during the composting process.
Tumblebug’s human-centred design approach ensures the system is replicable and scalable, with the long-term aim to create ‘cookie-cutter’ mushroom farms that can be deployed on other estates and farms around the UK.
Sylvie Verinder, Founder and CTO of Tumblebug, said:
“Tumblebug was founded to demonstrate to the world that we must, and can, go beyond sustainability to create a regenerative economy. We are honoured to be given the opportunity to demonstrate our Recover – Rotate – Regenerate circular economy model at this prestigious UNESCO World Heritage site. We look forward to building the human-centred design project and delivering the carbon data evidence of its impact with the incredible Blenheim Team.”
The project’s mushroom farming component is being delivered in partnership with Urban Farm-It, a UK-based fungi innovation partner that will supply the spawn and support best practices in small-scale gourmet mushroom cultivation.
Why It Matters
This farm represents a real-world blueprint for how heritage estates and rural businesses can lead the way in sustainable food production and carbon capture — without compromising on quality or economic viability.
By transforming waste into premium food and soil-enhancing compost, the Blenheim-Tumblebug model delivers:
- Local, traceable food production
- Emissions reduction through waste diversion
- Regenerative soil inputs like biochar
- Energy capture and reuse
- Economic opportunities for rural innovation
And with plans to share the model more widely, Blenheim’s mushroom farm may soon become a beacon of sustainable farming across the UK.
