Because bees are not very good with cold temperatures, they will stay inside their hives for most of the winter. While they may seem inactive during this time, bee season begins in mid-winter, as the days start to become longer. However, while bees are focusing on reproduction and building the colony, they still stay inside until much later. So when do bees come out?
It's not until much later into spring that bees begin to emerge from their hives and start to pollinate flowers. The need for bees to appear outside of a colony happens because of several different factors.
The temperature is easily one of the most significant factors in when bees come out. Bees need warmer temperatures to survive, so they often won't emerge until the chill of winter has faded. Depending on the weather, bees may appear from their hives earlier or later in the spring, when things are warm enough for them to survive.
Need for Food
Since collecting nectar from flowers is how bees can produce food, running low on stores of honey will often spur bees to come out of their hives. When bees need to go and collect food will depend on how well they stocked up during the fall and how many new bees they've produced while breeding.
Unfortunately, sometimes hives do not have enough food to last until the weather is safe for them to come out. This situation can cause problems for the colony, where there are too many bees for the available supply of food. Beekeepers need to pay close attention to their hives to ensure that the bees can survive until the weather improves.
With these factors in mind, the approximate time for bees to come out tends to fall between March and April, depending on the area and the climate. April is much more likely, as the weather isn't always acclimating enough during March and pollen supplies may not be readily available. As spring progresses into summer, a hive of bees will have much better access to flowers to produce their food supplies.
In addition to foraging for food, bees can also exit a hive when their current one becomes overpopulated. This process involves a queen leading half of a colony to search for a new area to create a new home. In the old hive, there are several special eggs, which hatch into new queens, that then fight for the right to rule the colony. Swarming can happen anytime during bee season.