Although the late summer has just started turning into autumn, beekeepers already have to consider the winter: They have a lot of work now, preparing their honey bee hives for the next overwintering period. “With good preparation, it is possible to keep bees fit and help them survive the cold season,” says Peter Trodtfeld, bee expert and beekeeper at the Bayer Bee Care Center in Monheim, Germany. “That is the precondition for them to expand as a healthy colony in spring.”
During the time when honey bees do not forage externally, they need sufficient food resources. Depending on how much honey is left in the combs, beekeepers can feed them with sugared water, beebread or syrup. “The challenge is to determine the right amount. Feeding the bees during the winter is not easy,” says Trodtfeld. As a beekeeper, he needs to know his bee colonies very well. Therefore, he weights them, for example, and determines the amount of food that the bees stored in their hive. During the winter a beehive needs 16 to 20 kilograms of food. Additionally, Trodtfeld counts the number of individual bees to estimate how strong and healthy his colonies are. Only if they are in good condition do they have the chance to survive the winter months. “I dissolve weak colonies and put two weak colonies together to build a strong colony,” explains Trodtfeld.
Honey bees also have to be protected from invaders and pests. An effective Varroa treatment is particularly important in late summer and autumn of the year. Otherwise, the parasite can reproduce and spread again rapidly in the remaining brood cells of the bee larvae until the winter. “In countries like Germany, a Varroa treatment using formic acid is not effective enough in autumn. Only when the outside temperature is at least 20 degrees Celsius will the concentration of the formic acid vapor in the beehive be high enough to be effective against Varroa mites,” explains Trodtfeld. The mites’ infestation can also be controlled using licensed varroacides, followed by observing how effective the treatment was by looking for Varroa on the base plate or Varroa floor. “However, now I cannot stop the viruses and diseases that the parasites might have transferred previously. That is why the Varroa treatment has to be done very early”, says Trodtfeld. He also has to protect the bees from invading mice, who like to nest in the warm beehive. Therefore, he installs a grid to keep them out. Trodtfeld wants his bee colonies to be healthy throughout the next winter.