Store Swiss chard in a plastic bag or airtight container in the refrigerator. To regulate moisture, wrap greens in a damp paper towel and do not wash until just before use. Chard is relatively hearty and will stay fresh for a week or longer if stored properly.
To freeze Swiss chard, wash leaves thoroughly and cut away stems. Steam or blanch in boiling water for two minutes and immediately place in a bowl of ice water. Dry leaves and transfer to a freezer-safe airtight container for freezing.
Chard can also be dehydrated and crushed or ground into a powder for sauces and smoothies. To dry, wash leaves and cut away stems, then place in a single layer on dehydrator trays and dry for 2-3 hours. If you don’t have a dehydrator, dry chard in the oven by baking at the lowest temperature setting for 60 to 90 minutes or until dry.