When selecting a cabbage for freezing, select one that is solid and feels heavy for its size, suggests HGTVGardens. The outer leaves should have a good color and should not be dingy or yellow.
To freeze cabbage, start by adding the cabbage to a solution of 1 to 3 teaspoons of salt and 1 gallon of water. Allow it to soak for 30 minutes to remove any bugs. Next, rinse the salt water from the cabbage, remove the outer leaves, and cut the head into wedges, keeping the core intact.
Blanch the wedges in ice water for about 90 seconds, remove them from the ice water, and place them in a colander to drain. Place the cabbage wedges individually on a cookie sheet and place them in the freezer for 12 to 24 hours. The wedges can be stored together in a large freezer bag or in individual, meal-sized portions.
For best quality, remove as much air as possible from the bags and do not overpack. When using the blanching method, cabbage can be stored for up to 14 months. Cabbage can also be frozen without blanching, but should then be used within 8 weeks. Frozen cabbage is a great addition to meals and can be used in side dishes, as well as in soups and stews.