Heirloom Watermelon Seeds. Citrullus lanatus. Non-GMO. Open Pollinated. (F1). Heirloom. Disease Resistant. We have a great selection of Heirloom Watermelons. The plants produce good yields of heirloom watermelons. Try growing some Heirloom Watermelon. Excellent choices for home gardens, Farmer's Markets, market growers, greenhouse production, open field production, and commercial growers.