MadCow expounded:

That seems unlikely as they fruit freely in southern England: your
summers are much hotter than up here, and if your winters were too cold
the tree would die.

Actually it turns out Mom got several medlars on her tree this season.
The tree is marginally hardy, she mulches it and burlaps it for the
winter.
--
Ann, gardening in Zone 6a
South of Boston, Massachusetts
e-mail address is not checked
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