The invention provides seed and plants of spinach hybrid RX 06681651 and the parent lines thereof. The invention thus relates to the plants, seeds and tissue cultures of spinach hybrid RX 06681651 and the parent lines thereof, and to methods for producing a spinach plant produced by crossing such plants with themselves or with another spinach plant, such as a plant of another genotype. The invention further relates to seeds and plants produced by such crossing. The invention further relates to parts of such plants, including the leaf and gametes of such plants.