Dutch horticulture introduces new greenhouse crops

Published on
June 5, 2020

Changes in social demands and the coronavirus crisis creates the need for more local food production. That is where greenhouses come in; tomatoes and bell peppers, the largest crops in Dutch greenhouses, will have to make room for vanilla, black pepper, and even papaya trees. There are very few limitations in horticulture according to senior researcher dr. Wouter Verkerke: ‘Plants love greenhouses’.

Changes in social demands

In the last six years social demand for food and products has been changing: natural ingredients and pesticide-free products are ‘hot’. Consumers are also more aware of environmental impact and prefer local products with a lower carbon footprint. With the coronavirus crisis this demand is increasing even further. ‘This is the opportunity for horticulture’, Verkerke says. His group at Wageningen University & Research started a programme called The Greenhouse Pharmacy. They focus on the production of non-traditional plants and crops in greenhouses such as tropical fruits, food ingredients like vanilla and plants used for medicine.

Marketing plan

While growing plants in greenhouses might not the greatest challenge, Verkerke stresses that we cannot just grow crops randomly. ‘You need to be sure that people will want to buy the product’, he says. ‘Marketing is essential’. Produce crops pesticide-free is one possible strategy. Also new products or services can add value.

The Greenhouse Pharmacy focusses on getting the most out of one plant and therefore have minimal waste. ‘That means we try to find ways to harvest fruits for retail, leaves for cosmeceuticals and the remaining flowers for massage oil’, Verkerke explains. While that may sound simple enough, there is a lot more to it, Verkerke warns. ‘It requires the right genotype of plant, the right conditions and the right cultivation process’.

About dr. Verkerke

Wouter Verkerke

Wouter Verkerke (PhD) is senior researcher flavour and founder of the flavour lab at the business unit Greenhouse Horticulture in Bleiswijk. Currently, he is a business developer for The Greenhouse Pharmacy. Verkerke studied biology in Amsterdam and did a PhD on the coevolution of tropical Figs and Fig wasps, based on field work in Makoukou (Gabon). After defending his thesis, Verkerke joined the Glasshouse Crops Research Station in Naaldwijk, working on quality of glasshouse vegetables. This work lead to the establishment of the current Flavour lab and research group in Bleiswijk.

Vanilla and black pepper

Currently, the Netherlands imports most of its black pepper and seventy per cent of it contains large amounts of pesticides. ‘Not only consumers oppose this, but companies are not allowed to use products when the pesticide levels are above a certain threshold’, Verkerke explains. Verkerke and his team managed to grow black pepper in greenhouses, without pesticides.

Vanilla comes from an orchid flower native to Mexico. While this orchid is grown in large quantities in Madagascar and Ile de la Reunion, there simply is not enough of it in the world. Therefore, it is often replaced by a synthetic variant. Verkerke himself prefers the natural vanilla flavour: ‘Once you have tasted the real vanilla, you will never want to go back to the chemically produced vanilla flavour’. Luckily, this may be an option for more people, since The Greenhouse Pharmacy managed to grow the vanilla orchid in greenhouses. ‘If we can do this on larger scale, we could stabilize the vanilla market’, Verkerke says.

Papaya tree in greenhouses?!

The possibilities do not stop at vanilla and black pepper. Even papaya trees can be grown indoors, Verkerke claims. ‘At first I was not convinced we would manage’, he admits. The solution? Dwarf trees. These small trees still produce high quality fruit and can easily be grown in greenhouses. ‘Greenhouses are a new arena for crop physiology’.  

Evolution of greenhouses

This is not the first time greenhouses in the Netherlands ‘evolve’. Approximately seventy years ago, table grape were the main product grown in greenhouses. Due to competition of the southern European countries, Dutch horticulture evolved to growing tomatoes. These transitions are often created by crises or when social demands change.

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