Peat-Free Growing Media Faces Resistance And Innovation In Equal Measure

Green sphagnum moss close up with blurred background

As the UK moves toward a peat-free future, substrate specialist Catherine Dawson reflects on progress and resistance, highlighting advances in innovation, shifting mindsets, and the irony of using living sphagnum moss as an alternative to the peat it would one day become.

Across the global horticultural landscape, the role of peat in growing media is the most pressing sustainability issue facing UK growers. Can traditional practices continue in a world that increasingly demands environmental responsibility? For Catherine Dawson, Senior Associate at Melcourt Industries Ltd., the answer lies in science, innovation, and a steady push for change. In recognition of her contributions to horticultural science and sustainability, the Royal Horticultural Society in the UK recently awarded her the prestigious Veitch Memorial Medal. FloraCulture International sat down with Dawson to discuss the evolving role of substrates and what it really takes for growers to leave peat behind.

Catherine Dawson, Senior Associate at Melcourt Industries Ltd., was recently awarded by the Royal Horticultural Society with the prestigious Veitch Memorial Medal.

Performance Matters: What Growers Need

At the heart of any professional grower’s needs is consistency. “A growing medium must perform to the same high standard from one product batch to the next,” Dawson explains. However, a high-quality substrate must also exhibit specific physical and chemical characteristics beyond uniformity. These include good drainage, aeration, water retention, low density, freedom from pests and diseases and stable pH and salinity levels. In the modern era, when corporate social responsibility must be accounted for, substrates must attain high environmental and ethical standards. Increasingly, this means producing growing media from locally sourced materials with a minimal environmental footprint.

A Convenient Past, a Challenging Future

Historically, peat bogs—abundant throughout Europe—supplied a reliable and inexpensive source of growing medium. After World War II, the rise of containerised plant production made peat a dominant substrate ingredient, valued for the air-filled porosity of its structure, low pH, and nutrient neutrality. Dawson describes peat as a “blank canvas” on which growers could paint the requirements of their crops. Even early on, though, bark was introduced to ameliorate the structural integrity of a peat substrate, setting the stage for the first peat-reduced mixes and opening growers’ minds to alternatives.

Innovation Rooted in Forestry

Melcourt Industries, where Dawson has played a pivotal role for over three decades, was among the first to explore peat-free alternatives seriously. The business has close ties to the forestry industry and has always used forestry by-products in its products. Their award-winning SylvaGrow® range utilises composted bark and wood fibre, each with unique characteristics. Notably, Melcourt avoids using the widely adopted “extruded” wood fibre, preferring instead to focus on other forms of composted wood to deliver consistency and structure.

The Pitfalls of Green Waste

Green waste is a product commonly introduced into peat alternatives. While appealing in theory, Dawson warns of its inconsistency. Its properties vary with the seasons and geography, and it tends to contain soil, increasing the density of the final product. Additionally, it may introduce variability in pH and nutrient content, a challenge for commercial growers who demand precision.
The Responsible Sourcing Scheme (www.responsiblesourcing.org.uk/) is an initiative supported by industry stakeholders helping to shape informed decisions about substrates in the UK. The scheme was devised to ensure that peat, with its well-recognised environmental disadvantages, was not simply replaced by other products just as bad, but not as well understood. The scheme uses a colour-coded traffic light system to rank growing media ingredients by environmental impact, enabling easy comparison. One revelation from the scheme, perhaps counterintuitive, is the relatively low footprint of coir, sometimes criticised for the distances it travels to reach Europe. The scheme reveals that coir, when responsibly sourced and processed, may offer a sustainable component in blends, particularly when combined with local materials.

New Hope for Peat-Free Blends

Melcourt regularly receives proposals from innovators hoping to contribute new materials to the peat-free movement. Most fall short due to consistency, availability, or environmental performance issues. But recently, one material has captured serious attention for its extraordinary water-holding capacity and ability to be cultivated sustainably. In trials, it has proven effective at up to 40 per cent by volume in growing media blends. The product in question is Sphagnum moss—the very plant left to live out its life in boggy land eventually turns to ‘peat’. Dawson is optimistic about its potential to become a mainstream component in ‘peat-free’ substrates. There is a certain irony in the fact that a whole industry could develop to grow sphagnum moss as a constituent in peat-free substrates!

Supply Meets Demand, But Where’s the Policy?

Today, professional-grade peat-free substrates are widely available in the UK, with supply keeping pace with steadily increasing demand. Melcourt’s portfolio of products serves both the amateur and professional markets, and the company’s reputation continues to grow. While the UK government has expressed a desire to eliminate peat from horticultural production by 2030, no legislation has yet been implemented to deliver this ambition. Dawson believes this is a missed opportunity. “We could have achieved that goal,” she asserts, noting that UK producers are fully capable of meeting national needs.

A Question of Mindset, Not Feasibility

According to Dawson, the slow uptake of peat-free growing media is not due to technical barriers but psychological ones. “Growers are naturally cautious; change is hard,” she says. Yet she’s quick to point out the industry’s adaptability in other areas, such as pesticide reduction and the adoption of Integrated Pest Management (IPM). These examples of industry flexibility give her confidence that widespread change is possible. So why the hesitation with peat-free substrates? Age may play a role: “Younger growers are more willing to make the switch,” she observes. Their training often includes sustainability as a core value, making the transition more intuitive.

Lessons from the Past, Optimism for the Future

Early missteps did not help. Poor-quality products in the amateur market and higher prices for early peat-free options created scepticism. But that landscape has changed. Today, a robust supply chain provides quality ingredients at competitive prices, making costs less of a barrier than ever before.
Reflecting on the roots of resistance, Dawson recalls a key moment in 1989: the “Disappearing Peat” conference. Friends of the Earth called for an outright ban, while industry leaders pushed for a phased approach. “That hardline stance created division,” Dawson says. “If we’d taken a more gradual path, we’d be much further along by now.” That early polarisation caused distrust, with many growers doubling down on peat’s perceived necessity. Dawson believes a collaborative, science-led approach could have spurred earlier innovation and broader acceptance.

The Road Ahead

Despite past tensions, the future of peat-free growing media looks increasingly promising. With science-led innovation, a growing body of supportive legislation, and champions like Catherine Dawson leading the charge, the industry is well on its way to a more sustainable future. The path forward may still require persistence and education, but Dawson’s work proves that change is not only possible—it’s already happening.

This article was first published in the May 2025 issue of FloraCulture International.