how do you plant onions , do you cut off the bottoms and plant the roots or do they have to be planted as sets?

This post was made over a year ago. Not sure why you're asking about growing info now. Pregnant onions are not the same as edible onions.

http://homeguides.sfgate.com/soil-pregnant-onion-prefer-64660.html

For info about growing real onions check the allium and/or vegetable forums.

Rodney