Do you have other citrus? How are the bees in your yard? I found this info on EDIS.

"Fruit produced on trees in solid plantings of
Minneola are likely to be seedless (or nearly so),
while trees in mixed plantings will typically have
7-12 seeds due to the influence of cross-pollination.
Minneola is not strongly self-fruitful and yields will
be greater when interplanted with suitable pollenizing
cultivars such as Temple, Sunburst, or possibly
Fallglo."

Lisa

Here is a link that might be useful: Minneola Tangelo

I have only one citrus tree on my entire property and none of my neighbors have any.

Should I plant anothe Minneolo or one of the varieties mentioned above?