Collards are a super hardy vegetable that freezes well. I have had great success freezing collards, and have done so for years. Here are a few tips for freezing collards: -Wash and dry the collards thoroughly. I like to use a salad spinner to get them really dry. -Remove the tough stems. I just cut them out with a knife, but you could also use a food processor or a mandoline. -Roll the collards up like a cigar and then slice them into thin strips. -Place the strips into a freezer bag and label with the date. -When you're ready to use the frozen collards, just place them in a pot with some water and simmer until tender. You can also add them directly to soups or stews.