The story of Ron

‘Puzzling over data, regions and harvesting periods’

Ron van Ruijven is production specialist for lettuce. In conjunction with his colleagues from the Logistics and Quality departments, he is responsible for Rijk Zwaan being able to supply the seeds that customers need. The fact that seeds are natural products presents considerable challenges.


“Each year, our season begins with scheduling the new production activities; per variety, we estimate how many new seeds we think we will need and where best to grow them. In order for us to be able to harvest seeds from a plant, the plant first has to develop shoots. That requires specific conditions; the slower a variety grows, the more it struggles to ‘shoot’. Because we’re doing more and more breeding in warmer climates, we’re also increasingly transferring the seed production to countries outside of the Netherlands.”


“To enable us to respond quickly to customer demands, we make use of the opposite seasons. So during the winter in the Netherlands, we can run a complete production season in Australia for example. In the Production department, we’re actually continuously puzzling over sowing data and production regions. We have to take account of things like crop rotation as well as the burden of disease and a region’s climate. In Chile, for example, the rainy season starts on 1 April so everything must be harvested by then.”

“The harvesting period can be a bit of a puzzle too sometimes, because some plants don’t yield their seeds easily – you can only harvest them when the sun shines. And in the case of other crops that release their seeds more readily you need darker conditions; if the sun comes out even briefly you have to stop harvesting immediately. So the challenge lies in making the most efficient use of the day.”

Expanding knowledge

“We’re continuing to expand our knowledge about seed production and harvesting all the time; we’re constantly working together with our colleagues from Seed Technology to explore how we can further improve the yield and quality. We look at things like the optimum plant density and the tying method, for instance, and we investigate how we can make a plant shoot more easily or more quickly. For multileaf lettuce, for example, we discovered that it helps if you let the side shoots grow.”

“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 our assortment at Rijk Zwaan and we also regularly develop new types – each one with its own approach. You’re never finished learning in this job!”

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