Sweet refrigerator pickles

Ingredients

2 pounds pickling cucumbers, sliced 1/2 inch thick on the diagonal (about 8 cups)
1 medium Vidalia or other sweet onion, sliced 1 inch thick
2 celery stalks, sliced 1/2 inch thick on the diagonal
Coarse salt
2 cups sugar
1 cup cider vinegar
1 teaspoon celery seed
1 teaspoon mustard seed

Directions
1. In a colander set over a medium bowl, toss cucumbers, onion, and celery stalks with 1 1/2 teaspoons salt. Set aside to drain, 30 minutes, tossing occasionally. In a small bowl, combine sugar, vinegar, celery seed, and mustard seed; stir until sugar is dissolved.
2. Divide cucumber mixture among clean jars or airtight containers, and pour vinegar mixture over. Refrigerate at least 8 hours (or up to 2 weeks).