From cultivation trials to retail shelves

Elise Wieringa is the sustainability manager at Intratuin, the Dutch franchised garden-centre chain that operates 72 stores: 55 in the Netherlands, three in Belgium and 14 in Germany.

As a leading advocate for sustainably grown plants, Wieringa has more than 30 years’ experience spanning business development, management consultancy, recruitment, product development and sustainable project management. In this fci Q&A, she explains why greener-grown lavender represents an important step towards aligning one of the most popular garden perennials with the triple bottom line of people, planet and prosperity.

Why is reducing chemical crop protection in lavender important now? “Our initial mission was, and still is, to expand the nation’s garden space by 50%. That prompted the questions: What makes a good garden? And what makes a good plant? Is it simply about visual attractiveness, or is it about choosing the right plant?

A good plant should be grown without pesticides, support biodiversity, be resilient, and benefit both people and nature. This discussion started in 2014. Since then, together with Tuinbranche NL, the Dutch trade association for garden retail and garden centres, we have made significant progress. Notably, we have reduced the use of neonicotinoids and phased out the active ingredients listed in Greenpeace’s ‘GP9’ and PAN’s 'Toxic 12’.

However, we believe that is not enough. We also need residue-free plants. In a nutshell, that is what our ambition of reaching 70% chemical-free plants by 2030 is all about.”

Investigative journalism also encouraged Intratuin to act, didn’t it? “Yes, it did. Reducing pesticide use has been one of our key sustainability priorities for many years. Residue testing on garden plants by organisations such as PAN, Greenpeace, and Dutch television consumer shows, including Radar and Kassa, made us realise that it was time to turn our plans into action.”

Why lavender? “Consumers particularly associate lavender and buddleia with bees and responsible gardening. These plants are therefore regularly tested by NGOs.

Lavender also represents a significant sales category for Intratuin. Producing residue-free lavender delivers a double benefit: it helps protect pollinators while bringing us closer to our goal of having 70% chemical-free plants.

Another important factor has been the collaboration across the entire supply chain, involving breeders, propagators, three of the country’s largest lavender growers, researchers, trade associations and garden retailers. Acting together is essential if we want to achieve meaningful change while preserving lavender’s positive image.”

Changing cultivation and retail

What is Intratuin’s role? “Intratuin takes on a supportive and encouraging role. Delphy, the project coordinator, keeps an eye on timelines and objectives. Together, we want to ensure that we can continue selling lavender with complete confidence.

Helping people understand why we are doing this project is key. PFAS and pesticide contamination have become major environmental issues in the Netherlands and elsewhere. We need to protect our planet, wildlife and people.

The project benefits growers by demonstrating that further pesticide reduction is inevitable. If they want to remain credible and trusted, they must continue adapting their production methods.”

Why are Delphy’s evidence-based trials important? “For growers, overcoming what is known as the status quo bias is not always easy. Naturally, many growers are cautious about adopting new cultivation methods because they fear uncertainty and losing control. That is why reducing the guesswork through independent trials before introducing new techniques in commercial nurseries is so important.

Change is deeply personal and often difficult. Systemic change is even more challenging because it requires coordinated action across the entire industry.”

Might lavender grown under the new cultivation protocol look different on the retail shelves? “The lavender itself may not change dramatically, but residue-free plants may look slightly different from conventionally grown ones. Consumers may also need to adopt a different mindset. A small insect or a few leaf spots can actually be proof that the plant has been produced naturally.”

How ambitious is the goal of 70% chemical-free plants? “Very ambitious. Not every plant has to be organically grown. Within the 70% chemical-free target, some plants will be organically grown and certified, while others, such as residue-free lavender, may still use synthetic fertilisers but no chemical plant protection products.

The organic plant category is growing, as are our sales. However, producing organic perennials remains challenging. Residue-free lavender is not automatically certified organic unless a grower chooses to undergo certification. I expect that process will take another couple of years.”

Measuring progress

How is progress measured? “The project’s objectives closely align with the MPS-GreenerGrown programme, which focuses on minimising environmental impact while producing commercially viable plants.

MPS-GreenerGrown complements MPS-ABC, which measures business sustainability, and MPS-ProductProof, which focuses on product reliability. They provide transparency about the use of plant protection products at nursery level. The programme uses a three-star system to indicate the level of chemical crop protection products used. We hope that the three participating lavender growers will qualify for at least one GreenerGrown star next year.

Progress is also monitored by testing cuttings and plants throughout the project. This approach resembles the minimum residue level sampling we already carry out on incoming plants.

Fortunately, we increasingly see fewer residues from substances such as the Greenpeace GP9 and PAN Toxic 12 lists, although traces can still occur. Sometimes residues originate from contaminated water, substrate or neighbouring farms rather than deliberate applications.

We therefore operate a comprehensive monitoring system. If we sample unauthorised or unwanted residue levels, we discuss the results with the grower. At higher concentrations, it becomes increasingly likely that the substances were applied directly. Even then, our objective is not to terminate business relationships. Regulations, even within Europe, differ, so transparency is essential.

The broader lessons will be shared to inspire other growers. I always encourage growers to understand what is happening beyond their own nursery boundaries and which plant protection products neighbouring growers use.

I also want to emphasise that all information shared within the project remains confidential. We provide a safe environment in which growers can learn and improve.”