Dilute 1 can orange juice. In a 9x9 serving dish or pan add water. Sprinkle Knox's unflavored gelatin over the top and let stand for 2 minutes to allow the liquid to absorb the gelatin. Add 1 cup hot orange juice to the softened gelatin.
Then add 1 cup cold orange juice. Stir well until gelatin is dissolved and place in the refrigerator for approximately 20 to 30 minutes until it begins to slightly set.
Add bananas, walnuts and celery to the cooled gelatin. Place in refrigerator until the gelatin sets, approximately 2 to 3 hours.
For a sweeter version, add honey or sugar.