Pollination of pumpkins by bumblebees

With the Flevopolder’s (the Netherlands) pumpkin fields starting to bloom, it’s time to release bumblebees into the crop. Today, 20 July, Gerard de Pee from Agrifirm and Frank Druyff from Koppert worked together to install the Natupol Boosters at various growers. Natupol Booster is a large bumblebee colony in a special hive designed for outdoor crops. Extra ventilation ensures that the colony suffers less from condensation or extreme heat. After release, the workers immediately start pollinating the crop.

Frank Druyff explains, ‘Two bumblebee boxes per hectare are needed to ensure optimum pollination. These must be spread across the plot. As the crop is still low in height, we always make sure the bumblebee boxes aren’t in the full sun. Putting the hive in a crate shields it from the sun and prevents the bumblebee colony from overheating, which would make the workers less effective at their job.’

Koppert has been testing bumblebee colonies in pumpkins for several years. More and more pumpkin growers are gaining first-hand experience with bumblebees and are very pleased with the results. The quality of the pumpkins is more uniform, and the use of Natupol Booster also has a clear added value in terms of shelf life. These benefits are even greater in regions that have relatively few natural pollinators.