I had to make it up, Michelle, because I couldn't find any English equivalent of "lover of autumn." And it's still not quite right. The Greeks seem not to have had a unified sense of the season of autumn. My lexicon distinguishes between ὀπώρα ("the part of the year between the rising of Sirius and of Arcturus (i.e. the last days of July, all Aug., and part of Sept.), the latter part of summer") and φθινόπωρον ("the waning of ὀπώρα (also called μετόπωρον or the season following ὀπώρα), autumn"). But I couldn't go with phthinoporophile!

Granted, if I were willing to mix my ancient languages I could say autumnophile, but I try to resist that.

Apparently, ὀπώρα sometimes refers to the fruit of late summer, so it marks abundance, while φθινόπωρον (φθίω being "to decay, wane") signifies the time when harvest abundance is ending.