Why would fruit die during its best growing season. Pictures please. Any of my fruit that starts in fall is doomed.

Where are you located? In ground or in container? Can be so many different reasons a tree does not keep the fruit. Picture would be nice

How old are your trees? Young trees often cannot hold fruit thier first few seasons. When you say the fruit dies, does it fall off when they are super small or do they grow to a decent size then wither?

my Manderine tree is 8 years old . for 5 years it flowered late summer ,cropped mid winter ,nice and sweet . than for the last 3 years it flowered in the spring some fruit would wither in the small size . some would grow large, than wither, in the extreme heat we have here in Australia 45 C , 110 F . its planted in the ground this whole time i have owned the plant.

thanks for your response