The old rule of many beekeepers is to take the bees from the cellar
when the soft maples are in bloom. This is an excellent rule in
localities where there are trees of this species. In general, in zone 1
the right time to take the bees out of the cellar is about the time of
the spring equinox (March 21).
In choosing a time for the removal of the bees, the beekeeper again
should watch the weather maps closely. He should choose a time
when a high-pressure area is just passing and at the approach of
a well-defined low-pressure area. At such a time the weather will
be cool, not permitting the bees to fly, but at the time of the
low-pressure area the weather will become warmer, allowing the good
flights, which are then badly needed.
If the bees are taken out at a time when they can fly at once--and some
beekeepers prefer this--they should be taken out in the early morning,
so that they can have a good flight before night. Bees should not be
taken from the cellar at a time when they can fly only a little, but
they should either be taken out when they can not fly at all or at a
time when they can fly freely almost at once. Bees in good condition
rarely fly freely unless the outside temperature is as high as 60° F.