Clean your spinach and dry completely. The easiest way to do this is to wash the spinach well and then place it in a salad spinner to easily get rid of excess water.
Then, place the spinach on paper towels or dish towels to fully dry. Once dry, you can divide the spinach into separate freezer bags or place it all on in one bag together.
Squeeze as much air out of the bag as you can and zip it tight. Then, lay it flat in the freezer so it freezes evenly and doesn't take up much space in the freezer.
Making Spinach Cubes
Place spinach and coconut water in blender or food processor. Blend until smooth.
Then, pour the spinach puree into clean ice trays and place in the freezer. Once the cubes are frozen, pop them out and store them in a large plastic bag or airtight container in the freezer.
Take one or two spinach ice cubes out at a time and include them in your favorite smoothie recipe.
Notes
Freezing fresh spinach in a bag will last up to a year. Make sure to squeeze as much air out as possible or vacuum seal the bags. Check it periodically for freezer burn so it doesn't go to waste. If you see ice crystals beginning to form on the spinach, use it soon!The frozen spinach ice cubes will last in the freezer for about 3 months.