How to protect bumblebees in cold

When temperatures drop during the winter months, bumblebees face challenges in surviving the cold conditions to maintain their productivity. We understand the importance of creating the ideal conditions for bumblebees to thrive and optimize their pollination activity. To ensure the best performance of bumblebees, it's crucial to maintain their hive temperature between 28-33 °C. They have their own clever ways of regulating this temperature, either by ventilating during warmer temperatures or incubating the brood when it gets colder.

Balancing pollination activity and climate

To achieve the best pollination results, it's essential to allow the majority of bumblebees to focus on their pollination activities, rather than regulating the hive's internal climate. Different temperatures can affect the behavior of bumblebees:

  • 8-11 °C: Bumblebees will start foraging, actively pollinating your crops
  • < 0 °C: When it's extremely cold, all bumblebees will remain inside or around the hive to incubate the brood. It's crucial to protect the brood during such conditions to avoid damage

Keep in mind that the impact of climate on pollination and colony quality is also time-sensitive. The longer unfavorable conditions persist, the greater the impact on the bumblebees and their performance.

Right climate for bumblebee pollination in greenhouses

In tunnels or greenhouses, the morning temperature needs to rise quickly to reach the minimum 24-hour temperature of 15 ºC for optimal plant development. When your crop is healthy and the average 24-hour temperature is at least 15 ºC, you can ensure that there won't be any issues with the foraging activity of the bumblebees, leading to efficient pollination.

Placement of hives in low temperatures

During the colder months, from half November until half of February, strategic hive placement becomes even more critical. Here are some key tips to ensure bumblebee colonies thrive in low temperatures:

  • Warmth is key
    Place the hives in the warmest part of the tunnel/greenhouse, ensuring they catch the morning sun. Make sure the hive is in a sheltered environment.
  • Sunlight exposure
    Position the hives on the side that receives the most sun during cold periods, maximizing their exposure to sunlight.
  • Elevated placement
    For optimal temperature control, place the hives above the crop.

Managing humidity in winter

While dehumidifying tunnels/greenhouses in winter, it's essential to keep an eye on the bumblebees. Sometimes, worker bumblebees may get lost through the vents and won't be able to return. To mitigate this, consider using netting whenever possible, or you can temporarily collect the worker bees in the hive for a short period using our Wireless Beehome System just prior to dehumidifying.