Red Onion Seeds

Red Onion is prized for its striking deep ruby-to-purple skin and crisp, ringed flesh tinged with pink. Its flavour is milder and sweeter than yellow onions, with just enough bite to keep things interesting, which is why it is the go-to choice for slicing raw into salads, layering into sandwiches and burgers, pickling, or caramelising on the grill where its colour and sweetness really shine. As a short-day, cool-season variety, it is well matched to Egypt's mild winter growing window.

Planting

Onion is a cool-season crop, and in Egypt the practical approach is to raise it in a nursery. Sow seed in autumn, from mid-September to mid-October, with mid-October sowing tending to give firmer, higher-quality bulbs than earlier September sowing. The optimum soil temperature for germination is 15-25 C, and seedlings usually emerge in about 2-3 weeks (roughly 15-25 days). When starting seed in the nursery, sow about 1.9 cm deep; for direct sowing outdoors, sow 0.6-1.3 cm deep once the soil starts to warm. Choose a spot in full sun, since onions need it for best growth. Because Egypt sits at a low latitude where bulbing is triggered at only about 11-12 hours of daylight, use short-day varieties such as the Giza types; long-day temperate onions would only make leaves and never form bulbs.

Transplant the seedlings once they are pencil-thick, about 30-35 days after sowing (and up to 6-8 weeks in some systems), which falls around mid-November. Egyptian research at the Shandaweel Experiment Station found the best yields when short-day transplants were set on 15 November rather than in February. Set transplants about 5 cm deep, spacing plants 7.6-10 cm apart in rows 20-46 cm apart (FAO gives 0.3-0.5 m between rows and 0.05-0.1 m between plants). Wider in-row spacing, up to about 15 cm, produces larger bulbs, while closer spacing yields smaller ones. In the cooler Nile Delta keep to the October-November transplanting window; in warmer Upper Egypt the same mid-November transplanting works but maturity tends to run a few weeks earlier, so do not delay sowing late into autumn.

Fertilizing

Aim for a soil pH of 6.0-7.0 that is rich in organic matter. Before planting, work fertiliser into the top 15 cm or so and apply phosphorus and potassium according to a soil test. Through the vegetative winter period, side-dress with nitrogen during growth; once bulbing begins in late winter, stop applying nitrogen, because excess nitrogen delays bulb maturity and leads to soft bulbs. Onion is also sensitive to soil salinity, a real concern in parts of the Delta, so use good-quality irrigation water and well-drained beds.

Care

Keep the soil consistently moist, near field capacity, providing about 2.5 cm of water per week and wetting to roughly 30 cm depth; the total seasonal water requirement is about 350-550 mm. Onions are most sensitive to water shortage at transplanting and during bulb enlargement, around 60 days after transplanting, so do not let them dry out then. Once the bulbs reach full size and the tops begin to fall, stop watering. If you direct-seeded, thin the plants to 7.6-10 cm apart before they crowd one another or begin to bulb. Watch for onion thrips and onion maggot (onion fly), and for diseases such as neck rot, basal and Fusarium rot, pink root, downy mildew, purple blotch and white rot; avoiding excess nitrogen and rotating crops helps keep disease down. Bulbs develop through the cool winter and enlarge as daylength increases in late winter and early spring. Harvest from roughly March to May, when about half the tops have fallen over and dried, the necks have softened, and papery outer skins have formed.