Ailsa Craig onions Seed ( long-day ) asian vegetable

A Spanish onion, Ailsa Craig, is large and sweet with a mild taste and grows best in USDA zones 3 through 9 with 14-16 hours of full sun. Onions (Allium cepa) are cool season biennials, members of the Amaryllidaceae family, which includes garlic, leeks, chives and scallions. Onions started from seed store better than sets, but mature later. Bulbing onions are dependent on day length for bulb production; short-day onions produce bulbs when they receive 11-12 hours of daylight, long-day onions need 14-16 hours (latitudes north of 35º), and moderate day onions like Walla Walla and Gladstone fall in between these. Soil Nutrients and Requirements Onions prefer soils rich in organic matter that are well-drained. Optimal pH is 6.2-6.8. They cannot tolerate acid soils, especially in early stages. 80 lbs/A nitrogen is recommended. Sidedress 4-5 weeks after planting. High levels of sulfur in the soil will increase pungency. Best results come from selecting a bed with the least weed pressure po