FREE: Famous Vidalia Sweet Onion Seeds (20)

Zone 6 your best bet is Onion seeds like the Vidalia Onions cause they are "Short day" growing. To start your seeds up there, You should start them from seed in a greenhouse or indoors because they do need warmth to germinate. Once they get to 1 inch above the soil you can transplant them outside. For sweeter tasting onions you need to plant them in a sandy or soil that doesn't retain a lot of water. And water them often because the soil doesn't hold the water. The reason for this is to wash away as much sulfur, doing this makes the onion sweeter cause it has a lower sulfur content. Cold Weather is no problem for "Short Day" onions. Even light snows won't affect the onions. If you get a lot of snow just use a milk jug or 2 lt soda bottle cut off the top and put over the tops of the plants. This isn't for keeping it warmer it's to keep the snow from packing the onions down where they don't receive any light. Onions require a certain amount of sunlight, as long as they get it or in this case not to much like summer days they will do great. If you have any other questions just let me know :)