The oldest preserved records relating to the cultivation of onions and onion seed date from 1914. In his note book, Cornelis de Groot jotted down the sowing and planting dates and the amounts. Cornelis de Groot’s father-in-law had given him a good variety of onion, and taught him the basic principles of plant selection. This mastery of “onion selection” has been passed down through five generations and has now been a family activity for more than 125 years.

After World War II, the activities became increasingly professional, triggered by the inclusion of the ‘Grobol’ selection on the official Dutch Variety List. When two sons of Cornelis de Groot joined forces with their brother-in-law Jan Slot in 1955, the enterprise De Groot en Slot was born. From the 1960s onwards breeding onion varieties became ever more refined due to hybridisation. The cooperation with Bejo dating back to 1970 signalled the first step on the road that would turn the company into the leading supplier of onion seed in West-Europe. This growth continued, not only in Europe, but far beyond. In the meantime, onions and shallot seed from De Groot en Slot en Bejo find their way all over the globe.