When do you prune a pear tree?

This would depend on the type of pear, and also the tree form ("Bush" tree, dwarf pyramid, cordon, espalier and sometimes fan.)

Then you have to consider the age of the tree and your reasons for pruning it (shape-formation, thinning of overcrowded spurs, rejuvenation etc.)

Basically, however, pruning is usually done in winter unless you have a very young tree that hasn't fruited yet and are performing formative pruning. Then the time for that is in mid-summer.

This is if you live in the U.K. or a place with a similar climate.
When do you prune a pear tree?
After all the fruit has been picked and before any flowers form.
Reply:Most pruning is done early spring before the sap starts to rise.
Reply:WHE N THE PARTRIDGE FLYS SOUTH..WAIT UNTIL THE LEAVES ARE GONE.