The story of Ron

‘Analysing data, regions and harvesting periods’

Ron van Ruijven is Production Specialist for Lettuce and Endive. Together with his colleagues from the Logistics and Quality departments, he is responsible for ensuring that high-quality seeds are available for supply to our customers all over the world. Seeds are natural products, which makes seed production a challenging process.


“Several times a year we examine our production planning and decide for every variety whether it is necessary to produce extra seeds. This depends on the sales forecast, the amount of seed we have in stock and the current production activities. We first decide how many seeds of each variety we need to produce, and then choose the best location and country to produce them. This depends on the climate, sowing period, cost price and permitted countries of origin. To enable us to respond quickly to customer demands, we make use of opposing seasons. For example, during winter in the Netherlands, we can run a complete production season in Australia and Chile. Right now, we’re producing lettuce seeds in many countries all over the world. The Netherlands, France, the USA, Chile, Peru and Australia are our main production countries, but we also produce smaller batches and conduct trials in a lot of other countries.”


Through our breeding programmes, we develop vegetable varieties for various production systems and climate zones. “Because we are breeding more and more lettuce seeds for warmer climates, we’re introducing slower bolting varieties. Slower bolting material requires specific production conditions so it’s a challenge for us to find the most perfect production location.” Rijk Zwaan’s Production department is continuously analysing sowing data and production regions, taking account of many different aspects such as crop rotation, the local climate and the susceptibility to diseases.


“Each specific variety needs to be managed differently. In the case of iceberg lettuce you need to de-heart the plant several times to stimulate bolting, and with multileaf you need to cut out the growing point and produce seeds on the side shoots. The harvesting period can sometimes be a bit of a puzzle too. Some production lines have to be harvested when it’s dry and sunny to extract the seeds from the plant, while in the case of other production lines high humidity reduces seed losses during harvesting.”


Expanding knowledge

“We’re expanding our knowledge about seed production and harvesting all the time; we’re continuously working together with our colleagues from Seed Technology to explore how we can further improve the yield and quality. We look at the optimum sowing date, the best plant density and the support method, for instance, and we investigate how we can make a plant bolt more easily or more quickly.”

“Seed production is always challenging, but in the case of lettuce the sheer numbers make it really complex. We already have a lot of varieties in the Rijk Zwaan assortment and we also regularly develop new types – each one requiring its own approach. There’s always something new to learn in this job!”

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