Better risk management, more biodiversity and reduction of pests and diseases – these are just some of the benefits of strip cropping. A number of organic farmers are putting this new cultivation method into practice in the Netherlands. One of them is agricultural company Erf BV, on one hundred hectares. The method is being trialled in other European countries too. “It results in more stable yields with the same amount of labour. But it also requires extra knowledge and a different approach,” says Dirk van Apeldoorn, lecturer and researcher at Wageningen University & Research (WUR).
Van Apeldoorn has been conducting research into strip cropping in the Netherlands since 2014. It entails dividing a field up into strips according to the width of the farm machinery, such as 3 or 6 metres or a multiple thereof. A different crop is planted in each strip. “Strip cropping is similar to the traditional farming method in China, and in the 1960s it was used in the USA for maize and soybean,” states Van Apeldoorn.
In the Netherlands, one aim of strip cropping is to help organic farmers achieve more stable yields, explains Van Apeldoorn: “For example, Phytophthora can ruin a whole field of potatoes. Strip cropping helps to stop it spreading.”
Risk management and biodiversity
The findings from many years of research show that this really does work in practice. The crop diversity helps to limit the risks and prevents the failure of an entire harvest of a monoculture. Moreover, planting the right combination of crops can reduce the pressure from certain pests, according to Van Apeldoorn: “Aphids are harmless to corn, for example. Those aphids attract spiders, beetles and parasitoid wasps, which then form a ‘standing army’ for the adjacent strip of cabbages, for example, which are susceptible to damage from aphids.”
The research confirms that strip cropping increases the biodiversity by attracting larger numbers and different sorts of insects than a traditional monoculture, and also by attracting birds.
More stable crop growth and comparable business benefits
Roy Michielsen, a grower at Erf BV, can confirm the abovementioned advantages. Erf BV leases 1,500 hectares of land from the Dutch government and is the biggest organic farming company in the Netherlands. It cultivates 15 crops based on a 1:8 rotation cycle and sells its products to major supermarkets and processing companies. In close collaboration with WUR, Erf BV has been putting strip cropping into practice since 2017 – initially on 40 hectares, which has since increased to 100 hectares.
Michielsen: “We organically grow potatoes, onions, oats, celeriac, parsnips/carrots, broccoli, grass/clover and broad beans in strips measuring six metres wide and 500 metres long. Because we work with both strip cropping and monocultures, we’re in a good position to compare the two approaches. Based on our experience, strip cropping results in stable crop growth, an increase in beneficial insects and – especially in potatoes – fewer issues with Phytophthora. From a business perspective, strip cropping is comparable with a monoculture in terms of both yields and costs. Although our employees were a little sceptical at first, they are all enthusiastic now. The simple fact is that it works well and it looks great.”
Complex puzzle with crops and varieties
Needless to say, strip cropping is not without its challenges. First and foremost, farmers need a lot of knowledge to choose the right crops. Michielsen: “It’s a puzzle that requires thorough planning. That was very time-consuming for us at first.” Van Apeldoorn adds: “The system is quite complex. Growers have to make the right combinations and register them carefully.
Different crops, and even different varieties, can react to one another. That places extra demands on the grower’s skills. Incidentally, lots of vegetable crops are suitable for strip cropping, including cabbages, pumpkins, leek, carrots, lettuce and spinach. In the Netherlands we’ve developed a course as part of the Bioacademy to help growers to make a crop plan. Unfortunately there’s nothing similar on an international level yet.”
GPS is essential
Besides knowledge, strip cropping also requires the agricultural company to take a different approach, Michielsen has discovered: “Ploughing doesn’t work with this system, which is why we opt for tilling instead. Our strips are six metres wide, so we can use almost all of our regular machines – providing that the tractors are fitted with GPS to support precision sowing. Besides that, water-reel irrigation isn’t ideal, which is why we switched to drip irrigation in 2020.”
More difficult to harvest root and tuber crops
He explains that it is more challenging to harvest celeriac, carrots and potatoes in strip cropping than in a monoculture. “We use the same machinery as for our monocultures, which means that we sometimes have to drive the tractor and tipper over the adjacent strip. That requires careful planning in terms of harvesting the crop in that adjacent strip. We’re currently managing to harvest all the crops, but we could further optimize that if we had different machines.”
Research projects in Europe
Strip cropping can be summed up as offering opportunities but also presenting some challenges. Van Apeldoorn firmly believes that the system will gain ground in the organic sector and also in traditional farming, both within and outside of the Netherlands. “The Netherlands is leading the way in strip cropping because the issues related to biodiversity and tackling pests and diseases are more urgent there than elsewhere. But some growers in Belgium have started using this strip cropping system, and we’re also involved in European projects in Denmark, Sweden, Germany, Austria, Italy and Switzerland. Of course, each project is adapted to the local conditions in terms of things like crops and strip width.”
“I believe that we need to transition to a different agricultural system: a robust, plant-based system with more crop diversity and more biodiversity. Strip cropping doesn’t have all the answers, but it does offer growers the chance to make a start.”
Would you like to know more about strip cropping?
Film – Strip cultivation in the experimental garden – Wageningen University & Research
Weblog – More nature in fields through strip cropping – Wageningen University & Research
Quotes:
“Aphids are harmless to corn, for example. Those aphids attract spiders, beetles and parasitoid wasps, which then form a ‘standing army’ for the adjacent strip of cabbages, for example, which are susceptible to damage from aphids.”
“Lots of vegetable crops are suitable for strip cropping, including cabbages, pumpkins, leek, carrots, lettuce and spinach.”
“I believe that we need to transition to a different agricultural system: a robust, plant-based system with more crop diversity and more biodiversity. Strip cropping doesn’t have all the answers, but it does offer growers the chance to make a start.”