"The temperature has to be above 14°C (57°F) for the pollen to be
fertile.
Did you have pollinators present?"
Yes, there were pollinators present and pollination on most of my
varieties was good, only the variety Major, which bloomed the heaviest,
set such a small crop. For this reason I'm tempted to believe it is a
varietal trait- produce a lot of blossoms as a young tree but only set
a few. Is this a tendency that some varieties have?