Onion

Onion (Allium cepa), known across Pakistan as pyaaz, is the country’s most widely grown bulb crop and the kitchen base of nearly every salan a Pakistani household cooks. POWO records the species as a Central Asian cultigen now grown across more than 80 countries,¹ and FAO ranks it as a major global vegetable on roughly 4 million hectares.² For a food-forest plot in Sindh, southern Punjab, or the Pothohar plateau it is the obvious cool-season groundcover to thread between taller crops.

Where it thrives

Onion runs across all four of Pakistan’s main growing zones, with the bulk of the national crop coming from Sindh (the Hyderabad belt) and Punjab. FAO puts the optimal mean daily temperature at 15 to 20 degrees Celsius and the cycle at 130 to 175 days from sowing to harvest, with bulbing triggered by daylength.² Day-length response splits the cultivars cleanly: short-day types (Phulkara, Swat-1, Dark Red) bulb on roughly 11 to 12 hours of daylight and suit Sindh and southern Punjab, while long-day types need 14 plus hours and only ripen in Gilgit-Baltistan or the upper KPK valleys.³ The crop wants a well-drained loam at pH 6.0 to 7.0 and is sensitive to waterlogging; brackish patches on the Indus coast need leaching before planting.²

Role in the system

Onion sits in the groundcover stratum as a short-stature, secondary-succession annual that fills the gap between taller vegetable and tree layers for one cool season. It is shallow-rooted with a feeding zone in the top 30 cm of soil, so it occupies a niche the deeper-rooting trees and shrubs never compete for.² Its strong sulfur volatiles repel a useful slice of insect pressure, which is why onion belongs in mixed beds next to brinjal, tomato, carrot, and lettuce rather than alone. It is not a fertility builder, so pair it with a nitrogen-fixing neighbour and feed compost into the bed before transplant.

Growing it

Decisions worth getting right. Match cultivar to latitude before anything else, then raise seedlings in nursery beds for six to eight weeks and transplant 10 cm apart in rows 30 cm apart once seedlings are pencil-thick.³ Water frequent and light, and stop irrigation 15 to 25 days before harvest so the necks dry and the bulbs cure for storage.² Pull when two-thirds of the tops have flopped over and have begun to brown, then cure in a shaded, airy spot for two to three weeks before bagging.⁴ Rotate the bed out of any allium for at least two seasons to break pink-root and white-rot cycles.

What you get

A well-irrigated crop yields 35 to 45 tonnes per hectare of cured bulbs, with water-use efficiency of 8 to 10 kg per cubic metre.² The bulb is the food: eaten raw in salad, browned as a base for nearly every Pakistani gravy, or pickled. Nutritionally onion carries quercetin, organosulfur compounds, vitamin C, and prebiotic fructans, a combination linked in the review literature to cardiovascular benefit, blood-glucose modulation, and antimicrobial activity.⁵

Sourcing notes

Buy fresh seed each year from a Pakistani seed company that lists the day-length class on the packet; saved seed from F1 hybrid bulbs will not come true. Good neighbours are carrot, lettuce, and brinjal in the same bed, plus a nitrogen-fixing companion such as berseem or chickpea on the windward side. Keep onion out of any bed that grew garlic, leek, or chive in the previous two seasons to dodge shared soil pathogens.

Sources

1. Royal Botanic Gardens, Kew (2024). “Allium cepa L.” Plants of the World Online.
2. Food and Agriculture Organization of the United Nations (2023). “Onion (Allium cepa).” FAO Land and Water Division, Crop Information.
3. University of Minnesota Extension (2024). “Growing onions in home gardens.” UMN Extension.
4. NC State Extension (2024). “Allium cepa (Onion).” North Carolina Extension Gardener Plant Toolbox.
5. Ahmed, H.G.M.D. et al. (2025). “Beyond seasoning: nutrients, bioactive ingredients and healthcare effects of Allium vegetables.” Frontiers in Nutrition.