A colony undertakes different tasks and has different priorities depending upon the time of the year. All of these tasks have the underlying purpose of allowing the colony to survive through winter (referred to as “overwintering”) and to perpetuate the species through reproduction.

Spring

March. Various trees begin producing pollen in March. They do not, however, produce nectar. If temperatures are above 55 degrees, foragers will begin collecting pollen. The influx of pollen into the hive stimulates the queen to begin laying eggs.

During the winter, the colony has been keeping itself alive by staying in a cluster with the workers activating their wing muscles to generate body heat and warm the cluster. The average temperature in the cluster in winter is about 70 degrees, but can go as low as 55. However, with the queen laying eggs in March, the colony will begin keeping the temperature around the brood at a constant 93 degrees. In order to maintain this constant temperature, the colony engages in significantly more shivering than it did during the winter months. The result is that the colony begins to consume approximately 8-10 pounds of honey per month during the Spring.

April. The bees are building up their population. Brood that was laid in March begins to emerge. The winter bees will begin to die. If the colony is healthy and resources are adequate, the colony will begin raising drones. Flowering plants usually begin to appear, which are an important sources of pollen and nectar for the Spring population build-up.

May. Population build up continues. The colony will continue to grow until the conditions are crowded enough that the colony’s natural impulse to swarm and create a separate colony takes over. (At this time, beekeepers with an established, overwintered colony need to take measures to either prevent swarming or deal with the consequences of a colony swarming.)

Summer

June to July. The hive population will continue to grow. At this point in the year, the nectar and pollen availability is both high and continuous. This is known as the nectar flow. Because of the amount of nectar that is available, bees are able to store more honey than they will need for winter. The colony will also increase its drone production.

August. The colony’s population will level off. This is the first step in the colony preparing for winter. Honey collection will continue. Drone rearing will stop. Workers will begin filling drone cells with nectar.

Fall

September. The colony population will begin dropping noticeably. The colony is trying to strike a balance between having enough bees to cluster and survive the winter, but not such a large population that it will eat all of the honey before nectar is available in the Spring. The queen begins laying the eggs that will become the winter worker bees. Drone expulsion begins.

October.

Winter. The bees that will occupy the hive during winter are emerging. The population of the hive has normalized to what its winter cluster size will be. Brood production will stop. The bees will begin to cluster as the ambient temperatures drop.

November through February. The queen does not lay eggs during the winter. The colony keeps warm by forming a ball, known as a “cluster.” The cluster will expand or contract based upon the internal temperature of the cluster and the temperature inside the hive. The average temperature of the cluster during winter is 70 degrees. To have the energy to maintain the necessary cluster temperature, the colony will consume approximately 5-6 pounds of honey per month. (A typical medium frame holds about 4 pounds of honey. A typical deep frame hold about 5-6 pounds of honey.)

During the winter, those bees that emerged in August through September will begin to die. As a result, about half of the bees that are inside the hive in October will die during the winter. If the ambient temperature allows, the workers will fly the dead bees out of the hive. If not, they will remain on the bottom board. Bees decomposing on the bottom board will eventually be covered with mold. Mold does not harm the living bees. However, the existence of dead bees can pose a risk to blocking the entrance to the hive.

A hive should be left alone during the winter. At most, during warm days, any entrance reducer can be removed and the bottom board cleaned off by inserting a long stick or a bottom board cleaning tool.