Educate Me On Fruit Trees

As poochie stated most fruit trees require at least a least one other cultivar (variety) that blooms at the same time to cross pollinate for good fruit production. They are not female and male plants per se. Same is true of blueberries.

Citrus, and a few others, are exceptions.

Chilling hours are also important, number hours of temperature below 45 F. So choose cultivars suitable for your area that meet the required chilling hours for your location.