I'm not sure what you mean by full dormancy. Apple trees stay dormant
throughout the cold season, until they come out of it sometime in Spring. You
can tell when the leaf buds begin to swell, or open. I am in the Midwest, but
also in Zone 5, and we have had very cold weather up to now, with the exception
of one day a week ago, when it got up to the low 50's. That was not enough to
get the trees out of dormancy. Apple trees, being very hardy, can be pruned
almost anytime during the dormancy period.

Don't forget that Winter pruning is usually for invigorating new growth, whereas

late Summer is better for things like opening up tree to more sunlight, because
any
cuttings then, will produce regrowth that will probably die back over the
following Winter.

Sherwin D.


Beth Pierce wrote:

I live in Northeastern Pennsylvania, a cold Zone 5, and have an orchard
of apple trees. In the past, I've pruned the trees in mid to late
February when they were in full dormancy, however, this year I sprained
my ankle and won't be able to get to them until late March. Is this
still ample time for pruning? What would be the absolute last day to
do so? Thank you for your help.