Flower industry carbon emissions vary sharply by growing system and supply route. In a 2023 life-cycle assessment covering production and delivery to Switzerland, emissions for three 20-rose-bunch systems ranged from 1.2 to 27 kilograms of CO2-equivalent. Greenhouse energy, freight choice, cooling, packaging, fertilizer, and water use all contributed to the measured differences.
Contents
- Rose emissions by production and freight system
- Energy demand and greenhouse production
- Production inputs and resource intensity
- Transport routes and logistics
- Packaging, cooling, and post-harvest operations
- Other life-cycle impact indicators
- Industry and marketplace benchmarks
Rose emissions by production and freight system
The clearest quantified comparison comes from Fairtrade’s Life Cycle Assessment Cut Roses, a 2023 study that modeled production and delivery to Switzerland. It compared average Dutch roses with Fairtrade Kenyan roses moved by air or ship. Each result below is expressed per bunch of 20 roses.
| Assessed system | Greenhouse-gas emissions | Study period and geography |
|---|---|---|
| Average Dutch roses | 27 kg CO2-equivalent | 2023 assessment; delivered to Switzerland |
| Kenyan Fairtrade roses, air freight | Not stated as an absolute value; 2.9 times lower than Dutch roses | 2023 assessment; delivered to Switzerland |
| Kenyan Fairtrade roses, sea freight | 1.2 kg CO2-equivalent | 2023 assessment; delivered to Switzerland |
Across the three assessed systems, the range was 1.2 to 27 kg CO2-equivalent per bunch. The study reported that Kenyan Fairtrade roses shipped by air had 2.9 times lower greenhouse-gas emissions than average Dutch roses. The Kenyan roses shipped by sea had 21.4 times lower emissions than the Dutch benchmark. Compared with air transport, shipping the Kenyan roses reduced greenhouse-gas emissions by 86%.
These figures describe particular systems and a specific destination, not every flower sold in every market. The source label for these measurements is Fairtrade, Life Cycle Assessment Cut Roses (2023), covering production and delivery to Switzerland: PDF.
Energy demand and greenhouse production
Non-renewable cumulative energy demand followed a similar pattern. Kenyan Fairtrade roses shipped to Switzerland required 19 megajoules per 20-rose bunch. Average Dutch roses delivered to Switzerland required 414 megajoules per bunch. The Dutch system therefore used 22 times more non-renewable cumulative energy than the Kenyan system using sea freight, and 6.4 times more than Kenyan Fairtrade roses transported by air. Shipping the Kenyan roses reduced non-renewable cumulative energy demand by 70% compared with air transport.
The production inventory shows why greenhouse operations matter. Average Dutch rose production used 1.143 kilowatt-hours of purchased electricity per harvested rose and 0.210 cubic metres of natural gas per harvested rose. These are 2020 Dutch greenhouse input data used in the 2023 assessment.
The early-2023 Kenyan producer data recorded 0.021 kilowatt-hours of purchased electricity and 0.001 kilowatt-hours of purchased renewable electricity per harvested rose. The Kenyan system recorded zero purchased heat and zero natural-gas use per harvested rose in that inventory. The difference is therefore not simply a question of whether flowers travel internationally: the production energy system is also central to the comparison.
The older Cranfield comparison, a 2007 study of roses produced in Kenya and the Netherlands for the British market, reported the Dutch operation’s main energy inputs as 800,000 cubic metres of natural gas and 1,200 megawatt-hours of electricity per hectare. Its figures belong to that study period and market context. Source: Cranfield, Comparative Study of Cut Roses for the British Market Produced in Kenya and the Netherlands (2007): report PDF.
Production inputs and resource intensity
Yield and crop characteristics differed between the systems in the Fairtrade assessment. Average Dutch rose greenhouses harvested about 328 flowers per square metre per year, compared with about 153 flowers per square metre per year in the Kenyan Fairtrade rose tunnels. Dutch roses averaged 55 grams per stem; Kenyan Fairtrade roses averaged 25 grams per stem.
The Dutch rose inventory used 8.45 plants per square metre, while the Kenyan Fairtrade system used 7.60 plants per square metre. The assessed Dutch plants had an approximately 8.0-year lifespan, compared with 6.3 years for the Kenyan Fairtrade plants.
Fertilizer inputs were higher for the Kenyan system in the reported per-rose inventory. Nitrogen fertilizer use was 0.294 grams per harvested Dutch rose and 1.044 grams per harvested Kenyan Fairtrade rose. Phosphate fertilizer use was 0.050 grams of P2O5 per Dutch rose and 0.357 grams per Kenyan rose. Potassium fertilizer use was 0.433 grams of K2O per Dutch rose and 1.262 grams per Kenyan rose. Kenyan Fairtrade production also applied 3.039 grams of unspecified fertilizer per harvested rose, while the Dutch inventory recorded zero in that category.
Water demand was 3.10 litres per harvested Dutch rose and 12.3 litres per harvested Kenyan Fairtrade rose in the inventory. Consumptive water use was 1.50 litres per Dutch rose and 5.1 litres per Kenyan rose. These resource figures should be read alongside the energy and freight results: a lower carbon result in this comparison does not mean every environmental indicator was lower.
Transport routes and logistics
The 2023 transport model included refrigerated road legs as well as international freight. For the Kenyan air-freight route, the farm-to-airport refrigerated-truck leg was 90 kilometres. For the Kenyan sea-freight route, the refrigerated-truck leg from farm to the port of origin was 565 kilometres.
The modeled international air leg from Nairobi to the Netherlands was 6,772 kilometres. The modeled sea leg from Mombasa to the Netherlands was longer at 11,721 kilometres. Despite that distance, the sea route produced the lower greenhouse-gas result in the assessment.
The Dutch farm-to-Aalsmeer refrigerated-truck leg was 169 kilometres. After the Kenyan air route, the modeled road leg to Aalsmeer was 8 kilometres; after the Kenyan sea route, it was 24 kilometres. From Aalsmeer to Zurich, the refrigerated-truck leg was 778 kilometres for each assessed supply chain. Source: Fairtrade, Life Cycle Assessment Cut Roses (2023), production and delivery to Switzerland: PDF.
The Cranfield comparison provides a second, older benchmark. For producing and delivering 12,000 Kenyan rose stems to a UK distribution centre, it estimated 2,200 kilograms of CO2 emissions. The equivalent 12,000-stem Dutch rose system was estimated at 35,000 kilograms of CO2. In the same comparison, the Kenyan system used 53,000 megajoules of primary energy, versus 550,000 megajoules for the Dutch system. Only 7,800 megajoules, or 15%, of the Kenyan primary-energy total was fossil energy, while more than 99% of the Dutch total was fossil energy.
Packaging, cooling, and post-harvest operations
Packaging and cold storage add measurable inputs after harvest. In the Fairtrade model, one packaging unit contained 25 bouquets of 20 roses, or 500 stems. The Kenyan packaging unit used 313 grams of plastic, compared with 1,250 grams for the Dutch packaging unit. It used 202 grams of paper, while no separately reported paper was recorded for the Dutch unit. Cardboard use was 2,368 grams for the Kenyan unit and 3,125 grams for the Dutch unit.
Cold-room electricity was 4.7 kilowatt-hours per Kenyan packaging unit and 12.5 kilowatt-hours per Dutch packaging unit. At the individual-rose level, the assessed Dutch system used 0.24 grams of plastic waste per harvested rose, compared with 0.010 grams in the Kenyan Fairtrade system.
The packaging results are tied to the 2023 packaging model and should not be generalized to every florist, wholesaler, or retail format. They do, however, show why a flower carbon assessment needs to include post-harvest handling rather than stopping at cultivation. Source: Fairtrade, Life Cycle Assessment Cut Roses (2023): PDF.
Other life-cycle impact indicators
The Fairtrade assessment also quantified impacts beyond climate change. Terrestrial acidification ranged from 0.006 to 0.026 kilograms of SO2-equivalent per 20-rose bunch across the three systems. Dutch average roses had 2.2 times the terrestrial-acidification impact of Kenyan Fairtrade roses transported by air, and 4.3 times the impact of Kenyan Fairtrade roses transported by ship. The Kenyan air-transport system had 2.5 times the terrestrial-acidification potential of the Kenyan ship-transport system.
Freshwater eutrophication showed another large difference: Dutch roses had 14 times the impact of Kenyan Fairtrade roses transported by air and 18 times the impact of Kenyan Fairtrade roses transported by ship. For marine eutrophication, Kenyan Fairtrade roses transported by air were 19% lower than Dutch average roses, while the Kenyan ship route was 31% lower than Dutch average roses.
These are impact-assessment results, not additional CO2 totals. Keeping the categories separate avoids treating acidification or eutrophication as if they were interchangeable with greenhouse-gas emissions. Source: Fairtrade, Life Cycle Assessment Cut Roses (2023), production and delivery to Switzerland: PDF.
Industry and marketplace benchmarks
The Cranfield comparison reported that CO2 accounted for 90% to 96% of the 100-year global-warming potential in its Kenya-Netherlands analysis. It also found that annual marketable-stem yields were almost 70% higher per hectare in Kenya than in the Dutch operation. Those findings come from the 2007 study and should be kept distinct from the later 2023 assessment.
Market infrastructure provides a separate operational benchmark. Royal FloraHolland reported 18,684 tonnes of CO2 emissions associated with energy consumed in 2020, down from 84,633 tonnes in 2019. Its reported electricity consumption was 109,908 megawatt-hours in 2020, compared with 116,137 megawatt-hours in 2019. Gas consumption was 9,885,569 cubic metres in 2020, down from 10,760,916 cubic metres in 2019.
Royal FloraHolland’s figures describe energy-associated emissions and consumption for the marketplace operation, not the full life cycle of every flower traded there. Source: Royal FloraHolland, Facts and Figures 2020: PDF.