One embodiment relates to seed and plants of inbred watermelon line WDL0090. Another embodiment relates to the plants, seeds and tissue cultures of inbred watermelon line WDL0090, and to methods for producing a watermelon plant produced by crossing such plants with themselves, with another watermelon plant, such as a plant of another genotype, or with vegetatively propagating said plant. Another embodiment further relates to seeds and plants produced by such crossing. Further embodiments relate to parts of such plants, including the fruit and gametes of such plants.