Introduce bumblebees 4-7 days before flowering begins. Once the flowers open, the bumblebees will start pollinating. Position the hive in the crop immediately after delivery, or a maximum of one day later, to allow the bumblebees to gather food.
Position the hives evenly throughout the plot for maximum results. The recommended number of hives is dependent on the crop and the presence of other pollinating insects.
Bumblebees and honeybees are able to complement each other's pollination work and can therefore be released into the same crops. Position a bumblebee hive at least 100 metres away from a honeybee hive, out of the sight of the honeybees. This is necessary because the honeybees may be attracted by the sugar water in the bumblebee hive, particularly if the main crop is not yet flowering.
After positioning, wait 30 minutes before opening the little doors to give the bumblebees to time to become calm again. Transportation and shaking movements can make the bumblebees restless.
Protect the bumblebee hive against very high temperatures resulting from direct sunlight, particularly in warm periods. Provide the hive with sufficient shade, for example by positioning it in the shadow of the crop.
Ensure that the underside of the hive is kept dry. Keep the hive entrance visible for humans and bumblebees during the flowering period. For instance, position the hive on a crate or on a stack of stones. Flowering weeds may be visited by bumblebees in addition to the target crop. You should therefore mow or cut down any flowering weeds in and around the area to be pollinated.
Protect the hive against strong winds. Position the hive in a sheltered spot, or weigh down the hive.
Position the hive horizontally, so that the bumblebees always have access to the sugar water supplied with the hive.
Use of pesticides
Exercise caution when using pesticides before and during flowering. Some pesticides can be harmful for pollinating insects and may also have long-term effects. Discuss the matter with your advisor. Consult the list of side effects, on paper or via the Internet. This list states how each product can be integrated with the use of bumblebees.