Believed to originate in Asia, onions have been used in every day life for centuries. Considered a cool season biennial, onions prefer to grow at cooler temperatures. Higher temperatures promote bulbing and curing. Plant onions early after the last hard frosts so that they can grow during the spring and early summer, producing bulbs as the temperature increases. CULTURE: For most onions, start indoors in late February to mid-March. SOIL: Fertile, well drained non-crusting soil. Onions will adapt well to muck soils. pH 6.0-6.8 FERTILITY: Onions use high amounts of nitrogen and potassium. Even moisture is required throughout its growth period. GERMINATION: 7-10 days at 70F/21C. Sow directly into final container (we use P-1201 cells and sow in 2 rows) 6mm/1/4" deep. Trim tops to 10cm/4" every week until transplanting. SPACING: Space transplants 6-8" apart in rows 16" apart. HARVEST: When onion tops start to fall over and bulbs have begun to form skins, pull up and allow to sun cure for at least one week. Do not leave out if there’s a chance of frost. STORAGE: When onions are dry, clip off the tops and place them in shallow boxes or onion bags. Place in a cool (a few degrees above freezing) somewhat humid place, 65-75% humidity. 200-275 sds/gm.
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