Yellow Onion Seeds

The Yellow Onion is the kitchen's true all-rounder: round, firm bulbs wrapped in glossy golden-brown papery skin over pale, ivory-white flesh. Raw, it carries a sharp, pungent sulphurous bite, but the magic happens in the pan; gentle cooking and slow caramelizing mellow it into a deep, savoury sweetness that builds the base of soups, stews, sauces and almost every cooked dish. Hard-skinned and long-keeping, it is the dependable everyday onion you reach for first.

Planting

Onion is a cool-season crop, so in Egypt the reliable method is to raise seedlings in a nursery. Sow in autumn, from mid-September to mid-October, choosing short-day varieties that suit Egypt's low latitude and form bulbs at only about 11 to 12 hours of daylight. Sow seed about 0.6 to 1.3 cm deep when sowing directly outdoors, or around 1.9 cm deep when starting in trays. The optimum soil temperature for germination is 15 to 25 C, and seedlings usually emerge within about 2 to 3 weeks. When the young plants are pencil-thick, roughly 30 to 35 days after sowing, transplant them around mid-November, setting them about 5 cm deep. Choose a spot in full sun and space plants about 7.6 to 10 cm apart in rows 20 to 46 cm apart; allowing the wider end of the in-row spacing gives larger bulbs while closer spacing yields smaller ones.

Fertilizing

Onions do best in soil rich in organic matter with a pH between 6.0 and 7.0. Before planting, work fertilizer into the top 15 cm or so of soil, adding phosphorus and potassium according to a soil test. As the plants grow through the cool winter, side-dress with nitrogen during the vegetative period to keep them building strong tops. Once bulbing begins in late winter, stop the nitrogen, because excess nitrogen at this stage delays bulb maturity and gives soft bulbs.

Care

Keep the soil consistently moist near field capacity, supplying about 2.5 cm of water per week and wetting down to roughly 30 cm deep; the crop is most sensitive to water shortage at transplanting and during bulb enlargement, around 60 days after transplanting. Once the bulbs reach full size and the tops start to fall, stop watering. Thin any direct-seeded onions to 7.6 to 10 cm apart before they crowd each other or begin to bulb. Watch for onion thrips and onion maggot, along with diseases such as neck rot, basal rot, pink root, downy mildew, purple blotch and white rot; avoiding excess nitrogen and rotating crops helps keep disease pressure down. Harvest when about half the tops have fallen over and dried, the necks have softened and papery outer skins have formed, with yellowing and toppling foliage signalling maturity, generally from March to May.