Watermelons can be stored uncut and unrefrigerated for about 10 days to 2 weeks. Place them in a very cool place to increase their storage time. If cut, watermelon will keep in the refrigerator for about 4 days wrapped tightly in plastic. Watermelon will decay if stored below 50°F (10°C) for more than a few days.
Raw Watermelon offers has a great amount of vitamins. Vitamin C, copper, Vitamin B5, Vitamin A, Vitamin B6, Iron, Vitamin B1, Potassium, and Magnesium to name a few.