How do you measure the sustainability of growing media raw materials?

Measuring the sustainability of growing media raw materials requires assessing performance across three pillars simultaneously: environmental impact, economic viability, and social responsibility. No single attribute, such as being peat-free, renewable, or locally sourced, is sufficient on its own. The measurement must be conducted at the system level, within a defined production context, using verified data rather than assumed material categories. The sections below address the most common questions growers, specifiers, and procurement teams ask when evaluating raw material sustainability.

What criteria define a sustainable growing media raw material?

A raw material can only be considered sustainable when it demonstrates credible performance across environmental, economic, and social dimensions simultaneously, within a specific production system. Labelling a material sustainable because it belongs to a category, such as peat-free, recycled, or bio-based, without measuring actual impacts, does not meet the standard. The term must be qualified, not assumed.

Research published in Frontiers in Horticulture in May 2026 identifies a foundational problem: the phrase “sustainable growing media” is widely used in industry and policy, yet it is frequently applied to single-attribute claims that ignore trade-offs, performance data, and system context. A material described as sustainable because it is renewable, for instance, may still carry significant processing emissions, perform poorly in certain crops, or create supply chain risks that undermine the grower’s economics.

Growing Media Europe and academic researchers have proposed a set of minimum conditions for responsible use of sustainability language in this sector. These include: considering all three pillars explicitly; specifying which pillar a claim actually addresses; framing sustainability at the system level rather than the material level; measuring impacts rather than inferring them from material categories; demonstrating functional and economic performance for the intended use; and making trade-offs and uncertainties explicit rather than presenting binary conclusions.

Kekkilä-BVB applies this multi-pillar logic through its Sustainability Compass, a structured framework covering environmental, social, and business dimensions that has been integrated into the product development process since 2022. Critically, the Compass requires a raw material to pass a fitness-for-purpose threshold first. If a material cannot perform its horticultural function reliably, its overall score is zero regardless of how well it performs on environmental or social indicators. This reflects a core principle: sustainability is a context-dependent outcome, not an inherent property of any material.

How is the carbon footprint of growing media raw materials calculated?

The carbon footprint of growing media raw materials is calculated using Life Cycle Assessment (LCA), following the Growing Media Environmental Footprint Guideline (GMEF), which aligns with the European Commission’s Product Environmental Footprint (PEF) methodology. The reference unit is one cubic metre of fresh growing media mix or mono-material as delivered to the client, assessed from cradle to gate for intermediate products and cradle to grave for consumer-facing products.

The GMEF Guideline, now in its second version published in September 2024, was developed with input from industry and an open public consultation. It enables all growing media producers to calculate environmental impact using consistent calculation rules and comparable impact categories. Growing Media Europe also operates an online LCA platform that allows members and stakeholders to apply the guideline in practice. The methodology has been integrated into broader horticultural frameworks covering cut flowers, potted plants, and fresh produce, enabling carbon footprint calculation across the full supply chain.

One important limitation of current LCA practice is that comparisons often evaluate equal volumes of material rather than equal use cases. A growing medium that performs more efficiently in a given crop, requiring less water, fertiliser, or growing time, may have a higher standalone carbon figure yet deliver a lower footprint per kilogram of produce. A holistic perspective that incorporates the growing medium’s influence on resource use throughout the crop cycle is essential for meaningful comparison.

Kekkilä-BVB uses the PEF methodology alongside the Ecochain LCA system to evaluate the footprint of its raw materials and logistics. A practical example of this approach in action: by switching block peat transport from road to rail between Sweden and the Netherlands, the company achieved a 40% reduction in CO₂ emissions in that logistics stream. The GMEF Guideline requires transport distance and mode to be captured as primary, site-specific data in any compliant assessment, which means generalised assumptions about logistics cannot substitute for actual supply chain data.

What’s the difference between renewable and non-renewable growing media raw materials?

Renewable growing media raw materials regenerate within a human-relevant timeframe and can be harvested repeatedly without permanent depletion. Non-renewable materials are extracted from finite geological or biological reserves that do not regenerate at a commercially meaningful rate. In practice, the boundary between these categories is more nuanced than a simple binary, and the distinction alone does not determine environmental impact.

Established renewable raw materials

Wood fibre, coir, reed canary grass, sphagnum moss, and miscanthus are among the renewable materials that have gained traction as growing media constituents. Wood fibre sourced from certified residual timber can be incorporated at 30 to 50 percent by volume in substrate blends with results comparable to peat, though higher proportions can restrict water and nutrient availability. Kekkilä-BVB commissioned a dedicated wood fibre production line in the Netherlands in 2025, drawing on PEFC-certified residual wood, with an annual capacity that supports the company’s target of sourcing half of its substrate blend raw materials from non-peat origins by 2030.

Reed canary grass, harvested annually in early spring from former peat production areas in Finland, offers a locally produced option with a low transport footprint. Sphagnum moss regenerates at approximately 10 mm per year, with a harvesting cycle of 20 to 30 years, and research confirms regrowth begins within a year of collection. Coir, a by-product of coconut processing, is classified as renewable and retains water well, though it is imported to Europe primarily from India and Sri Lanka, which introduces transport considerations into any carbon assessment.

Peat and the slowly renewable classification

Peat occupies a distinct position in this classification. Both the IPCC and the European Commission acknowledge that horticultural peat differs from fossil fuels and from conventional renewable biomass such as timber. Kekkilä-BVB and Neova Group classify horticultural peat as a slowly renewable raw material, recognising that it forms over thousands of years but is biologically distinct from mineral fossil resources. Approximately 58% of EU peatlands are degraded; these areas can be used for responsible peat production, and their rehabilitation afterwards converts them into carbon sinks.

The renewable or non-renewable label does not, on its own, determine a material’s environmental performance. Even renewable materials carry a carbon footprint through processing, transport, and energy use. The renewable classification is a starting point for assessment, not a conclusion about sustainability.

Which certifications and standards apply to growing media sustainability?

The principal quality and sustainability certifications for growing media raw materials are the RHP quality mark, Responsibly Produced Peat (RPP) certification, now integrated under RHP, and the EU Ecolabel for growing media and soil improvers. Each addresses different aspects of the supply chain and different raw material types.

The RHP quality mark is the primary certification for professional growing media, covering quality and safety requirements from raw material production through to delivery. RHP-certified substrates must meet defined standards for water uptake, air content, pH, electrical conductivity, and nutrient levels, as well as freedom from heavy metals, weed seeds, and pathogens. As of January 2026, RPP certification for responsibly produced peat has been fully integrated under the RHP umbrella. RPP ensures that peat is extracted from ecologically degraded areas and that post-extraction land use is planned responsibly, with High Conservation Value areas excluded from extraction. Kekkilä-BVB reported that 64% of its peat holds RPP certification, with a target of 80%.

RHP is also developing a certification scheme for responsibly produced coir. A concept scheme was piloted with five companies at eight locations, and Kekkilä-BVB has joined this sector initiative, though the final published standard had not been formally released as of mid-2026.

The EU Ecolabel applies to growing media and soil improvers as a product group, with current criteria valid until the end of 2030. It guarantees compliance with criteria aimed at reducing soil and water pollution, limiting heavy metal concentrations, and ensuring products are made from renewable and recycled materials. The EU Ecolabel is directly relevant to substantiating environmental claims under EU Directive 2024/825, which prohibits generic environmental terms such as “eco-friendly” or “green” unless claims are supported by specific, verifiable, and independently verified evidence. Businesses face significant penalties for non-compliance from September 2026 onwards. Self-made eco-labels and unverified trust marks are explicitly prohibited under this framework.

How do sourcing location and transport distance affect sustainability scores?

Sourcing location and transport distance affect sustainability scores through their contribution to a raw material’s carbon footprint and, separately, through their influence on social responsibility ratings. However, proximity to source does not automatically produce a lower environmental impact. Transport mode, load efficiency, and the energy source used in processing often matter more than distance alone.

A well-documented example illustrates this: shipping coir from India to a Northern European port can produce fewer carbon emissions than transporting composted bark by road from a domestic location, because sea freight carries far greater volume per unit of fuel than road haulage. This counterintuitive finding, confirmed by the Royal Horticultural Society, underlines why distance-based assumptions are insufficient in LCA. The GMEF Guideline requires transport distance and mode to be recorded as primary, site-specific data rather than estimated, precisely because these variables have material effects on the outcome.

Kekkilä-BVB’s Sustainability Compass incorporates transport distance and mode as a scoring element within the environmental assessment. Local production is scored favourably where it genuinely reduces transport emissions, as with reed canary grass harvested in Finland and processed at the company’s Parkano facility. However, the Compass also recognises that local production does not guarantee local raw material extraction: if inputs to a domestic manufacturing site travel long distances, a significant portion of the footprint is incurred before the “local” label applies.

Sourcing location also affects social sustainability scores. The Sustainability Compass uses the amfori BSCI risk index to assess the social responsibility of raw material origins, factoring in both the country of extraction and the country of processing. Raw materials sourced from lower-risk regions score more favourably on social dimensions, which means geography influences multiple pillars of a sustainability assessment, not only the carbon calculation. For guidance on how these assessments connect to broader sustainability commitments, Kekkilä-BVB’s sustainability framework provides the full methodological context.

What are the hardest sustainability trade-offs to measure in growing media?

The hardest trade-offs to measure in growing media sustainability are those that span multiple pillars simultaneously and resist reduction to a single metric. These include biodiversity impact, cross-sector competition for bio-based raw materials, and the gap between a material’s standalone environmental profile and its actual performance within a complete crop production system.

Biodiversity is perhaps the most significant measurement gap in current methodology. The GMEF Guideline’s Product Environmental Footprint method does not include a dedicated biodiversity impact category. Biodiversity effects are partially captured through land use, climate change, and eutrophication indicators, but these proxies do not cover the full picture. Direct measurement of species richness or genetic diversity at extraction sites requires site-specific ecological data that is rarely available at the scale needed for standardised comparison across raw materials.

A second structural challenge is that LCA comparisons typically evaluate equal volumes of growing media rather than equal production outcomes. A substrate with a higher per-cubic-metre carbon figure may still deliver a lower overall footprint per unit of crop if it supports faster growth, reduces water and fertiliser inputs, or extends the productive life of a growing system. Evaluating materials on volume alone systematically distorts the comparison in ways that disadvantage high-performing substrates.

Cross-sector competition for bio-based raw materials presents a trade-off that is difficult to quantify but increasingly consequential. Chemical, construction, and energy industries are competing for many of the same renewable feedstocks that growing media producers use. Availability is not static, and a raw material that is abundant today may face supply constraints as demand from other sectors grows. Kekkilä-BVB’s circular raw materials programme addresses this by developing locally sourced and side-stream materials that are less exposed to cross-sector competition.

Finally, single-pillar framing creates persistent measurement errors. Peat is frequently characterised as environmentally unsustainable based on global peatland statistics that do not reflect actual extraction practices or regional contexts. Conversely, alternative materials are labelled responsible because they are non-peat, without accounting for processing emissions, transport impacts, nitrogen immobilisation during use, or end-of-life handling. EU Directive 2024/825 reinforces why this matters in practice: from September 2026, claims that exaggerate environmental benefits or apply a positive attribute of one component to the whole product are prohibited. Accurate sustainability measurement requires the full system to be assessed, trade-offs to be declared, and claims to be precisely scoped. If your operation needs support navigating these assessments, contact Kekkilä-BVB to discuss how the Sustainability Compass and LCA tools can be applied to your specific growing context.

This content was generated with the help of AI and it may contain mistakes