- You will get 125 Seeds of Onion Seeds Red Grano Heirloom Vegetable Seeds. - Sunlight: Full Sun. - Life Cycle: Annual. - Watering: Medium. - Red Grano is a wonderful, all-round heirloom onion! With its crisp and mild flavor, the Red Grano onion is a great for cooking, is a perfect hamburger topping, and is delicious in salads. Being a short-day onion, the Red Grano is best suited for growing south of the Kansas/Oklahoma line. Let the medium sized, Vidalia-style Red Grano tantalize your taste buds!. - Plant seeds 3/8-1/2" deep in a germination medium; keep the soil moist, but not saturatedat 70-75 degrees. When the tops begin to droop, cut them off to 3", which will promote root weeks before the last frost or when the soil reaches at least 50 degrees F, transplant the seedlings 5-6" apart in rows 12" apart. For direct sowing, sow three seeds every inch in light, rich soil and full sun. Thin the seedlings 2-6" apart, depending on the desired size. Thinned onions can be transplanted or used for culinary purposes.