The process of plugging one nostril, and blowing air out of the other, in order to shoot out mucus. In order to make this technique successful, you must use great force, otherwise you will just look retarded when you have one nostril covered and are breathing heavily in front of your friends. But if you get that dang snot of of there...you will be known as a stud.
Jim had a nasty cold, and didn't have any tissues. He decided a farmer's blow would do lots of good, until he shot it on his girlfriend's prime rib.
Blowing your nose with out a tissue by pushing on one nostril and blowing out the other to get rid of boogers and snot.
When I am out running I don't carry tissue so when I need to blow my nose I just do a farmers blow.
The act of plugging one nostril while forcefully blowing the other causing the snot from the open nostril to shoot out onto the ground.
Brian was sick and congested however after his farmer's blow, his breathing became easier.
also applies to a bloody nose.
In the middle of a football game, he got a bloody nose, so he decided to use a farmer's blow. All the blood shot out and the rest clogged up.