There’s a strange humming noise in the warehouse fridge at Mertens, a horticultural products distributor in the south of the Netherlands. A closer look inside the chilled shelves reveals it’s coming from boxes of bumblebees. An unusual industrial product, certainly, but one that is vital in modern Dutch agriculture.

Thanks to intensive, high-tech methods and innovations in biological farming such as packaged bumblebees, the Netherlands has become the second largest exporter of agricultural products in the world. That’s quite a feat considering that the top exporter is the US, which boasts a landmass more than 200 times larger.

How did this tiny country transform itself from a barren, swampy underdeveloped land into the vegetable garden of the world?

The southern state of Limburg is a case in point. Impoverished and ravaged after the Second World War, hungry citizens began growing mushrooms in bunkers and trying to coax unproductive fields to yield food. In 1953, a local apple farmer called Jan Mertens began selling crop protection to enrich soil and fend off pests, increasing yields and paving the way for the intensive, highly mechanized and largely indoor agriculture in the region today. Because of the high cost of land and labor, Mertens and other key actors in the industry focused on horticulture — fruits, vegetables and flowers — rather than grains, which take up more space and yield less profit per square meter.

As a result of similar developments across the country, total agricultural exports from the Netherlands reached EUR 82.4 billion in 2015, around a fifth of total Dutch exports. It is now the world’s largest exporter of vegetables.

“The Netherlands is historically a very strong trading nation. It deals easily with other countries and has high-quality and very safe end products,” says Mart Verheijen, managing director at Mertens, which has now fulfilled its former managing director’s dream of becoming one of Europe’s most prominent horticultural product suppliers.

Mertens has grown rapidly over the past 50 years by offering a wider range of products than its competitors and by appointing trained agronomists as sales staff that specialize by crop, such as asparagus or soft fruits, rather than product categories, such as pesticides or soil enrichment. This means they can give honest and in-depth advice, and help farmers shift easily from chemical to biological products, which are increasingly demanded by consumers.

Another of Mertens’ strengths is its fast delivery, earning it a reputation as the Amazon of the horticultural world. Like the famous online retailer, Mertens promises next-day delivery for most of its products. The speed of delivery is very important for pesticides and fungicides, both chemical and biological, because pests and fungus can quickly destroy an entire crop if it is not treated soon enough.

What do Mertens’ customers have to say about their services?

My father started this farm growing lettuce, kohlrabi and gherkins. I grew up watching him farm and went on to study agriculture at university. In 1993, when I was 21, I took over the business. By that time, my father had started growing peppers, which is now my main crop. We grow about 13 million peppers a year and as much as 95% are exported: they end up in Japan, Germany, the UK, Sweden, Russia, the US and South America.

My father was a Mertens customer from way back. Now we get a lot of supplies from them, including biological solutions.

I take a lot of care about the quality of the product, of course, but I prioritize safety: what is sprayed on the peppers must be suitable for little children to eat. So I use almost no chemicals at all and want to use biological solutions as much as possible. For example, I use small packets of insects that eat aphids, insects that can ruin the crop. One supermarket asks for levels of pesticide residue that is 70% beneath the government standard — and they only want to find that on three peppers out of a whole batch. So it’s very strict, but thanks to Mertens we are able to meet those standards.

I used to be a technical engineer, but switched to running this strawberry farm after I got married to my wife, who is from a farming family. We cultivate about 100,000 kilograms of strawberries every season.

I’ve been a Mertens customer since 1993. I’m very grateful for their support in supplying solutions that don’t use pesticides and chemicals.

One of those solutions is the bumblebees. You can either use honeybees, which you rent from beekeepers, or you can buy bumblebees and they last for about seven weeks. The bumblebees are less effective at pollinating but they are out all day whereas the honeybees are more fair weather; they only come out when the weather outside is fine.

We grow the strawberries on a “table-top” system, which is so-called because the plants grow in a soil tray elevated to about chest-height. The system has many benefits: for example, water can be easily drained and 90% of it can be re-used. We also use a kind of fast-draining peat made from coconut shells. Because it stops the plant roots from getting waterlogged, which causes strawberries to mold, we don’t have to use any chemical fungicide at all.

The system also makes it much easier to pick the strawberries, so one person can pick up to 35 kilograms per hour, more than double what they can when they’re kneeling down to pick fruit from plants on the ground. Labor costs constitute about 40% of the price of strawberries, so this saving makes it easy to get a return on my investment into the table-top system.

We buy the plastic roof film, the irrigation pump, the tubes, the peat, the biological control and fertilizers from Mertens.

Mertens’ strawberry specialist agronomist, Jan Janssen, comes every two weeks to inspect the plants and give me advice. He recommended we use Thripex, which are little packets of bugs that eat strawberry mites and thrips, which are pests that can really ruin the plant.

Sometimes Jan tells us we’re doing just fine and that we don’t need to buy anything. I trust him because I know he’s got my interests at heart and isn’t just pushing products on us to make a sale.

Growing 100% organic cucumbers is quite difficult. But recently, we have been able to reduce chemicals and get close to that. I’m glad, because we have to respond to customers’ demand for biologicals.

We first started using biological products about 10 years ago, but we soon gave up because we didn’t have experience with them. Compared to pesticides, where you get results almost immediately after you’ve put them down, biologicals take a while and it takes some patience. We started using them again a couple of years ago because we now have a sales representative who has more experience with them and can give us better advice.

Mertens’ advisor sees a lot of customers so if he sees problems at one place he can tell us that we’re likely to see the same problem. So they know to look out for it and they can respond quickly or they can put in preventative measures. If we catch the problem too late then it is already too big.

I wanted to be an entrepreneur and it was my dream to be a mushroom farmer when I was 12 years old. For some reason I just really liked mushrooms. I was obsessed with them. Now I have a farm that produces 24,000 kilograms of mushrooms every week. We supply 30% of a big Dutch supermarket chain’s needs and also sell to France and Germany. Mushrooms are produced indoors in all seasons, so the farm is running 365 days a year.

When I started my business 30 years ago, we were using chemicals. Back then mushroom growers had whole cabinets full of chemicals and pesticides. But now, instead of spraying to kill diseases, we make the growing rooms so that it’s hard for illnesses to even start.

The Netherlands is famous for mushroom cultivation and some rooms in the Netherlands are quite big, as much as 2,000 ㎡ with trays going up so high in the sky that they need to use lorries to harvest them. And wherever you go in the world where mushrooms are grown, you can guarantee that they’ll have some growing equipment from the Netherlands.

I’ve known Mertens’ mushroom specialist, Rob Wilbers, for 30 years. The personal rapport we have is very important. Real partners stick around when there’s real problems, just like real friends. We had a problem with the soil one day, an issue with a small insect, and Mertens sent us the product to solve it on the same day. When we need something they are there immediately.

Mertens celebrated its 60th anniversary in 2013 and today it is the third largest products distributor for horticulture in the Netherlands, selling to 4,000 customers. It recorded sales of 57 million euros in 2015 and its profit has doubled in the past 10 years.

“We see the future very positively, because our customers have confidence in us as a company and know that we are there for them in the long term. Our strengths are our advice, our vast product range, and our fast delivery. Our customers know that will be the same in the future,” says Jan Schoeber, the other managing director who runs Mertens along with Verheijen.

The two have led the company together for 12 years and have both worked there twice as long as that. They have steered the company through turbulent times in the past five years in which the market consolidated and some rivals went bankrupt. Mertens was steady through the storm because of its diversification across segments and focus on customer relationships.

“We have to be independent to be able to advise the growers and sell the best products for our clients,” says Verheijen. “We want to have strategic conversations with our parent company Marubeni about which direction to grow in, whether to do M&A or grow organically, where the opportunities are and where the risks are, and how to take the next step.”

With growing demand for safe, high-quality vegetables, including biologicals, Mertens expects to see strong and steady growth in the years to come.

All information contained in this article is based on interviews conducted at Mertens in June 2016.