What season are bumble bees born in?

Bumble bees are born during the spring. Queens hibernate during the winter, and come out in the spring to start new colonies. They begin to lay eggs, and the larvae develop into adult worker bees. The colony will continue to grow until the fall, when the queen will lay eggs that will develop into new queens. The old queen and the workers will then die, leaving only the new queens to hibernate and start the cycle again the following spring.