You're not wrong - avocados planted from seed take anywhere from 5 to 13 years+ before they flower and produce fruit.

http://ucavo.ucr.edu/general/answers.html

We have a compost bin in the back yard where they sprout from seed spontaneously. I have grown a couple of trees and given some seedlings away to friends.

Fingers crossed, they bear fruit eventually. If not, they make a fairly fast growing tree (2m after 3-4 years) - although this week the leaves burn quickly in the summer heat if inadequately watered.

I have a large avocado plant that I grew from a pit. At only 2.5 years old, it's about 3 feet tall. Definitely won't be ready for fruit any time soon. Maybe when my grandchildren are born (for the record, I do not yet have children).

Yikes...I should have done the research first. I'll edit, thank you.