- You will get 401+ Seeds of Yellow Sweet Spanish Onion Vegetable Seeds. - Seller Notes: “Allium cepa. U.S. Grown Seed. Organic. Tested 1/23-Germination 94%. Packed 1/23.”. - Planting Time: 10 Weeks. - Soil Type: Loam, Peat, Sand. - Life Cycle: Annual. - USDA Hardiness Zone (°F): 9 (20 to 30 °F). - Soil pH: Neutral. - Watering: Medium. - Sunlight: Full Sun. - Spanish Onion-Making a recipe that doesn’t specify the type of onion? Go for yellow(Spanish). These all-purpose winners are basically the blue jeans of the onion world—versatile staples that we don’t know what we would do without. They can easily grow to over a pound each. Use them to add a tangy sweetness to soups, sauces, pastas and just about anything. Interesting fact: Spanish onions are actually a type of yellow onion, with a slightly more delicate, mild flavor. 400+ seeds per order. - Allium cepa. - Full sun. - Spring, soil temp 65F+.Fall. - SOW 1/4" deep. 2" apart. Keep Moist. - Germinates in 7 - 14 days. - Medium water. light fertilizer if needed. - Days to maturity - 120 - Spring planting. 170 - Fall planting.