I have an advocado tree I grew from a pit. It is 6 years old now. Since it is potted and has to stay that way (we live in Wisconsin), it is only about 4 feet tall. When it was in its fourth year it flowered. I read up on how there were male and female flowers. I tried to pollinate them. It didn’t take. So no fruit for us either. But I was so excited for the flowers anyway! It has not flowered in the years since.