Can greenhouse horticulture
really reach net zero?
By Ron van der Ploeg
For greenhouse growers who want to achieve climate neutrality, job number one is to reduce greenhouse gas emissions at the source. At the same time, some emissions are hard to eliminate entirely, particularly those arising from supply chains. This is where carbon removals, transparent emissions accounting and reliable footprint data can play a complementary role.
Greenhouse Sustainability argues that growers should first focus on reducing emissions within their own operations wherever technically and economically feasible. Only after these opportunities have been addressed should carbon removals be considered for the remaining, hard-to-abate emissions.
Carbon removals should complement—not replace—emission reduction
Reduction first, removal for the residual emissions The principle of reducing emissions at source is central to credible climate action. Greenhouse growers can often make significant reductions through changes in energy use, fertilisation, crop protection, water management and growing media.
However, achieving a 100% reduction through operational measures alone is extremely difficult. The Science Based Targets initiative (SBTi), for example, recognises the existence of residual emissions in its net-zero framework. Companies are expected to make deep absolute reductions across their value chains, while residual emissions that cannot yet be eliminated can ultimately be neutralised through carbon removals. SBTi Net-Zero Standard requires corporate decarbonisation (90%+) plus neutralisation of residual emissions via carbon credits.
This challenge becomes particularly significant when looking at Scope 3 emissions. These emissions arise elsewhere in the value chain and can include fertilisers, substrates, young plants, packaging, transport and energy-related equipment.
Growing media provide a good illustration. A grower may want to move away from materials with a higher environmental impact, such as peat, but the alternative must still provide the water retention, root support and crop performance required. The environmental impact of the alternative can also depend on how it is produced and transported.
For emissions that cannot currently be eliminated, greenhouse growers can calculate their remaining footprint and, where appropriate, finance carbon-removal projects. Greenhouse Sustainability offers ONCRA (Open Natural Carbon Removal Accounting)-verified carbon removals through its Bamboo Village project in Uganda, where bamboo is cultivated to remove CO₂ from the atmosphere.
The important distinction is that carbon removals should complement—not replace—emission reduction.
Carbon credits can provide finance for independently verified emission-reduction and carbon-removal projects beyond a company’s own operations, helping to support projects that might otherwise lack sufficient funding.
Avoiding the illusion of progress One of the main criticisms of carbon offsetting is that it could create the appearance of climate progress while a company’s own emissions remain unchanged or even increase. This risk makes transparent carbon accounting essential.
A company’s actual greenhouse gas inventory should be measured and reported separately from the carbon credits it purchases. Carbon credits should not be used to obscure increases in operational or value-chain emissions, nor should purchasing credits be presented as equivalent to reducing those emissions.
Carbon credits can nevertheless make a useful contribution to broader climate action. They can provide finance for independently verified emission-reduction and carbon-removal projects beyond a company’s own operations, helping to support projects that might otherwise lack sufficient funding. Depending on the project, they can also generate wider environmental and social benefits.
The key is therefore transparency. Carbon credits should be communicated as an additional climate contribution and, where appropriate, as a way of addressing residual emissions, not as a substitute for decarbonisation.
The principle of reducing emissions at source is central to credible climate action
Watch: Offsetting CO₂ emissions
Video by Greenhouse Sustainability
Turning footprint data into business decisions Reliable environmental footprint data can also help growers move beyond sustainability reporting and use environmental performance as a practical management tool.
Greenhouse Sustainability’s FloriFootprint Tool uses life-cycle assessment to identify environmental hotspots in a greenhouse operation. Depending on the crop and production system, these hotspots may include energy, crop protection or growing media.
The value of such a calculation is that growers can compare different scenarios before making a business decision. For example, they can assess how the footprint changes when switching to another fertiliser or crop protection product, changing growing media or using renewable energy.
The next version of the FloriFootprint Tool is designed to make these calculations faster and more user-friendly. It will also include a module through which growers can enter the costs associated with different sustainability measures. This allows an environmental scenario to be evaluated not only in terms of its impact on the footprint, but also in terms of its financial consequences.
This can help growers assess which measures offer the best balance between cost, yield and environmental performance.
The same data can provide value beyond the farm itself. A substantiated sustainability footprint can be shared with traders, retailers and other supply-chain partners, supporting more transparent reporting and enabling companies throughout the chain to work together on improvement.
The FloriPEFCR methodology is intended to make environmental-footprint results more comparable between products and provides a common methodology for environmental footprint calculations for cut flowers and pot plants.
Reduction versus offsetting: an economic decision? The economic argument is an important part of the debate. In practice, growers may face situations in which an emission-reduction measure has a higher upfront cost than purchasing carbon credits.
For example, if an energy-efficiency investment costs €80 for every tonne of CO₂ avoided while a carbon credit costs €40 per tonne, it may be tempting to choose the cheaper option.
Greenhouse Sustainability’s position is that this should not automatically lead to offsetting instead of reduction. Emissions should be reduced where doing so is technically and economically viable. Carbon credits can then be used to provide additional climate finance or to address emissions that cannot currently be avoided.
Moreover, the initial cost of a reduction measure does not necessarily reflect its full economic value. Investments in energy efficiency, renewable energy, fertiliser efficiency, water management or more precise crop protection can generate savings over time.
A switch from natural gas to geothermal or another renewable energy source, for instance, can potentially reduce exposure to volatile energy prices. More efficient use of fertilisers, water and crop protection products can simultaneously lower environmental impacts and operating costs.
The relevant comparison is therefore not simply the price of one tonne of avoided CO₂ against the price of one carbon credit. Growers also need to consider the investment’s lifetime, energy and input savings, operational risks, crop performance and future regulatory and market requirements.
Bamboo Village Uganda is currently expanding its infrastructure to produce biochar and bio-based building materials.
Who pays for sustainable production?
For growers, however, there is a broader commercial challenge. Sustainability investments can require additional capital and operational changes, while the benefits may be distributed across the entire supply chain. If retailers, traders and consumers are not willing to recognise these efforts financially, growers can struggle to recover the additional costs.
Sustainability does not automatically have to reduce profitability. Some measures can improve efficiency and reduce costs, while others can strengthen a grower’s market position by providing credible, measurable evidence of environmental performance.
A quantified sustainability score can help distinguish a grower’s production from competitors and provide supply-chain partners with reliable information rather than relying on general sustainability claims.
Ultimately, however, the transition towards lower-impact greenhouse production cannot be the responsibility of growers alone. If the sector expects producers to make substantial investments in energy, inputs and production systems, the economic value of those improvements needs to be recognised further along the supply chain.
This makes reliable footprint measurement increasingly important. Without credible data, it is difficult to show where emissions are coming from, which interventions deliver the greatest reductions, what those interventions cost, and who benefits.
For growers, the objective is not simply to claim climate neutrality. It is to understand where emissions occur, reduce what can realistically be reduced, address what cannot yet be eliminated, and ensure that sustainability becomes an economically viable part of the production model.
