LOL, I have to love people (wherever they may be on the planet) who think 50-68F is "winter." (that's not much cooler than my 'summer' !)
Unless it is some sort of decidedly un-hardy, tropical type of apple tree, it should be perfectly fine outdoors... they survive and grow here where I live, through -30F winters.
“Think occasionally of the suffering of which you spare yourself the sight." ~ Albert Schweitzer C/F temp conversion
(that's not much cooler than my 'summer' !)
