Disclosed is a seed of spinach hybrid RX 05991199, a sample of seed of said hybrid having been deposited under ATCC Accession Number PTA-13165. Also disclosed is a method for producing a seed of a hybrid RX 05991199-derived spinach plant comprising the steps of: (a) crossing a spinach plant of hybrid RX 05991199, a sample of seed of said hybrid having been deposited under ATCC Accession Number PTA-13165, with a second spinach plant and (b) allowing seed of a RX 05991199-derived spinach plant to form.