Icebox watermelon is a small variety of watermelon that typically weighs between 8 and 10 pounds. It became readily available to consumers in 2005. Because of its size, it fits well in the refrigerator, hence the name. An icebox watermelon -- like all watermelons --is best harvested when ripe. Expect to harvest an icebox watermelon approximately 78 days after planting, making sure it meets several criteria first to ensure it is ripe enough for picking.
Watch for the icebox watermelon rind to change from a bright green color to a dull green color.
Look at the stem where the icebox watermelon is attached to the vine. The curly tendrils that grow from the stem turn brown and become dry when the melon ripens, according to University of Illinois.
Lift up the watermelon. The area where it sits on the ground will be a creamy yellow color when the melon is ripe.