Watermelon Sugar Baby-This small, round melon is called an icebox type because it is petite enough to fit in the refrigerator. This widely adapted heirloom variety is solid, dark green on the outside with a bright red, firm and fine-grained flesh that is super sweet. Watermelon contains high levels of healthy antioxidants, making Sugar Baby a great sweet way to pack in good nutrition. Vines are compact. Plant about 4 feet apart.