Actions are needed on the water-hungry, pesticide-hungry, invasive-species spreading ornamental plant trade.

International trade in plants brings risks for both importing and exporting countries – including impacts on native ecosystems, hitchhiking invasive species and indigenous people being exploited. Some of these risks are reflected in the Kunming-Montreal Global Biodiversity Framework, adopted in 2022, to which the EU and all its member states are parties. This framework includes targets to ensure that the harvesting and trade of wild species is sustainable, safe and legal, and to minimise the impacts of invasive species on biodiversity and ecosystem services. There are also various EU agreements containing rules on trade and sustainable development and the EU Regulation on Deforestation-free Products, which mandates that traders of particular commodities in EU markets – including wood, cocoa and soy – must prove that their products do not contribute to forest degradation.

According to the authors of a new study, ornamental plants are a commodity which deserves more attention in risk assessment. Comprising cut flowers and foliage, live plants and bulbs, ornamental plants have a global export value of US$23 billion (€20.5 billion). Their trade has been steadily growing and changing in recent years, for instance with frequent changes in demand, emergence of new supply countries (e.g., Colombia and Ecuador) and practices (e.g., a shift to vegetative over seed propagation). The authors examine the risks and impacts of the trade, for both cultivated and wild-harvested plants, also considering global seizures of illegal shipments and interception of plant contaminants reported by the Netherlands and the United Kingdom.

The main impacts facing exporting and importing countries differ. Exporters see native species of wild plants affected by illegal harvesting, with orchids, cacti and succulents being especially vulnerable. While cultivation impacts native species less than illegal harvesting, it does not eliminate the threat to their conservation because it can raise demand for a species, facilitate smuggling, and may rely on wild source harvesting. The impacts of illegal plant trading are often undocumented and probably underreported compared to animal-based illegal trade, but the trade has been linked to the extinction of several native species in the wild – for example slipper orchids in Vietnam and Sprenger’s tulip in Turkey¹. 

High water use is another significant impact of ornamental plant growing. Floriculture can have exceptional demands on water – for example in India it was estimated to require 20 times as much water as cotton, and even more relative to some food crops. Production regions are often in developing nations, which are especially vulnerable to climate change, food insecurity and conflict related to water scarcity. Floriculture also uses significant amounts of pesticides and plastics, raising the risk of adverse health outcomes for flower handlers and of polluting the environments where flowers are grown. 

Accompanying these risks are impacts relating to waste, emissions, and food security. Cut flowers are a perishable product of no nutritional value, which generate lots of waste, highlighting the need for better supply chain management. The researchers found that the industry’s carbon footprint from production methods significant, including greenhouse energy needs, irrigation, peat fertiliser and transport. Flowers must be kept cool and transported quickly, increasingly at intercontinental scale. Also, allocating land to floriculture can remove it from local and indigenous communities and food producers, negatively impacting food security and socioeconomic stability in times of drought, and undermining local livelihoods. The study authors also contend that the ornamental plant trade does not sufficiently consider biopiracy or access and benefit-sharing, which was regulated in the EU as of 2014, to ensure that any benefits from the genetic resources and traditional knowledge of a country are shared equitably.

For importers, key risks concern biosecurity and invasive species, with a need to identify how species are introduced to importing regions. These risks were found to be slightly better understood but still insufficiently mitigated, especially in terms of biodiversity. 

Copious contaminants are still found in imported shipments, many of which, particularly insects and their eggs, cannot be identified at species or even genus level. For example, small vertebrates such as lizards are often missed during inspection, instead being noticed by members of the public after purchase. Invasive species can affect agricultural production and ecosystem functioning, may require pesticides to control, and for some insect pests may bring the risk of hybridisation, which can lead to pesticide resistance. 

Various ornamental plants are themselves invasive species and may threaten native plants. They may also introduce parasites, pathogens and zoonotic diseases to new regions via reptiles, amphibians, and insects in shipments – such events may be exceptionally rare, but the potential costs could be substantial.

The authors identifies many risks for importers and exporters in the fast-evolving, international ornamental plant trade and highlighted the need for proactive efforts to mitigate these risks. They suggested better standards and certifications were required to protect workers’ rights and reduce the trade’s harmful impacts on people, species and the environment. Despite regulation efforts, there remains substantial opportunity for illegal trade in wild plants, and for pests to travel to and settle in new areas. Better sanitary and inspection procedures – e.g., introducing plant passports or phytosanitary certificates – and restricting potting substrates may reduce risk, but efforts to reduce pests should not fall disproportionately on supplier nations.

Crucially, a lack of transparency and availability of data were limiting factors in the analysis, and this also impedes regulation and control measures. There is probably substantial illegal trade of ornamental plants, accidentally introduced species are often not fully identified, and data is incomplete, inconsistently recorded, and usually kept private by different agencies, they say. For effective regulation, policymakers require collated, standardised, accessible datasets so they can identify patterns and pathways of risk – so a strong focus on information gathering and sharing is also needed.

Footnotes

1. Hinsley, A., Willis, J., Dent, A.R., Oyanedel, R., Kubo, T., Challender, D.W., 2023. Trading species to extinction: Evidence of extinction linked to the wildlife trade. Cambridge Prisms: Extinction 1: e10.

Reference

Hinsley, A., Hughes, A. C., van Valkenburg, J., Stark, T., van Delft, J., Sutherland, W., and Petrovan, S. O. (2025) Understanding the environmental and social risks from the international trade in ornamental plants. BioScience 2024 0, 1–18.

https://doi.org/10.1093/biosci/biae124