# Onion (Allium cepa)

Canonical: https://plantguide.ae/plants/onion · Updated: 2026-10-29
Source: Plant Guide (https://plantguide.ae/plants/onion)

Onion · بصل  
vegetable · exotic · family Amaryllidaceae · grows 0.3–0.6 m tall, 0.1–0.2 m wide · moderate growth  
full sun · moderate water need  
Ratings for Dubai (1–5, 5 is best): heat 2 · salt 1 · drought 2 · shade 1 · ease of care 3  
Sow or plant: Sep–Dec  
Uses: edible, container

## Also known as

- **English:** Bulb onion, Common onion
- **Arabic (العربية):** بصل
- **Hindi (हिन्दी):** प्याज (Pyaz)
- **Urdu (اردو):** پیاز (Pyaz)
- **Malayalam (മലയാളം):** ഉള്ളി (Ulli)
- **Tamil (தமிழ்):** வெங்காயம் (Vengayam)
- **Tagalog:** Sibuyas
- **Bengali (বাংলা):** পেঁয়াজ (Peyaj)
- **Persian (فارسی):** پیاز (Piaz)

> **Advisory (caution):** A normal food for people, but the ASPCA lists onion as toxic to dogs, cats and horses. Keep pets away from the bulbs, tops and kitchen trimmings.

A slow winter bulb for Dubai raised beds: start in the nursery from September, plant out October to December, pull green onions early and lift the bulbs from March to May.

## About

Meet the onion, the crop that does most of its work out of sight. For weeks a bed of onions looks like nothing more than thin green spears, while below the soil each bulb swells a little more every day.

Its character is patient and tidy. Onions ask for sun, steady water and a short row of food each month, and they take up almost no room: a hand-width between plants is enough. You can pull a few young ones for salads long before the rest are ready.

What it brings is the satisfaction of lifting a harvest you can keep. Once the tops fall over, the bulbs dry in a shaded corner and go into the kitchen for weeks, long after the winter bed has been cleared.

Onions are the quiet, slow crop of the Dubai winter bed. The UAE Ministry of Climate Change and Environment's calendar lists nursery planting from September to November and field planting from October to December, and gives two harvest times, 150 days and 60 days. We read the shorter figure as green onions pulled young and the longer as full bulbs. The Ministry's Undersecretary named green onion among the crops residents should grow at home when the Plant the Emirates programme launched in October 2024, as Khaleej Times reported.

UF/IFAS explains the one choice that decides success. Onions are classed as short-day, mid-day or long-day by the hours of daylight they need to start a bulb, and at southern latitudes short-day cultivars do best in the autumn crop. Dubai lies at about 25°N, so look for short-day types on the seed packet or the set label. UF/IFAS says sets, small bulbs ready to plant, are quicker and easier than seed: set them 1 inch (2.5 cm) deep and 4 to 6 inches (10 to 15 cm) apart, with a foot between rows, feed with a complete fertiliser at planting and nitrogen monthly, and irrigate frequently. Bulbs are ready in four to five months, when about a quarter of the green tops have fallen over.

Onions mind salty water. FAO rates bulb onion as sensitive to salt, with a yield threshold of about 1.2 dS/m, one of the lower figures in its vegetable table, so use mains water on a drip line and fill the bed with sweet soil rather than native sand. After lifting, UF/IFAS says to cure the bulbs for a couple of weeks in a cool, dark, dry, well-ventilated place, then trim the tops and roots and store them somewhere cool and dry. A Dubai gardener profiled by Gulf News counts onions among the crops in her garden.

## Through the year

Onions start in the nursery from September and go into the bed from October to December, as short-day sets or seedlings. From November to March they get a monthly nitrogen feed and frequent watering. Green onions can be pulled from about two months after planting, and bulbs are ready after four to five months, from about March to May, when about a quarter of the tops have fallen over. Lift them, cure them for a couple of weeks in a cool, shaded, ventilated spot, trim the tops and roots, and store them dry. By April the average high is 34°C and the bed is cleared.

| When | What | Note |
| --- | --- | --- |
| Sep–Nov | Sow: Nursery planting | Ministry calendar: nursery September–November. UF/IFAS says sets are quicker and easier than seed; choose short-day cultivars. |
| Oct–Dec | Plant: Plant out | Ministry calendar: field planting October–December. Set 2.5 cm deep and 10–15 cm apart, with 30 cm between rows (UF/IFAS). |
| Nov–Mar | Feed: Monthly nitrogen | UF/IFAS: a complete fertiliser at planting, then nitrogen monthly, with frequent irrigation to keep growth steady. |
| Dec–May | Harvest: Green onions, then bulbs | The Ministry lists 150 and 60 days. Pull green onions young; lift bulbs when about a quarter of the tops have fallen over (UF/IFAS), then cure for a couple of weeks. |
| Apr–May | Heat stress: Lift before the heat | Bulbs planted in the Ministry's window finish by about March to May. Dubai's average high reaches 34°C in April and 38°C in May. |

## Care in Dubai

- **Watering in summer:** Not grown through summer in Dubai; the bulbs are lifted and cured by about May.
- **Watering in winter:** Water often enough that the soil never dries out, early in the morning from a drip line. Ease off as the tops start to fall over.
- **While establishing:** Keep the row evenly moist after planting out; UF/IFAS says to irrigate frequently to promote steady growth.
- **Soil:** Sweet soil rich in compost and well drained, in a sunny raised bed (UF/IFAS asks for well-drained soil high in organic matter). Flavour depends partly on the soil and the feeding, UF/IFAS adds.
- **Feeding:** A complete balanced fertiliser at planting, then a nitrogen fertiliser each month while the tops grow (UF/IFAS).
- **Pruning:** None. After lifting, trim the tops and roots once the bulbs are cured (UF/IFAS).
- **Planting:** Plant short-day sets or seedlings from October to December, 2.5 cm deep and 10–15 cm apart in rows 30 cm apart, in a spot with full sun.
- **Pests and problems:** Onion fly; Onion eelworm (nematodes); Fungal rots
- **Toxicity:** A normal food for people. The ASPCA lists onion (Allium cepa) as toxic to dogs, cats and horses: the toxic principle is N-propyl disulfide, and signs include vomiting, breakdown of red blood cells (haemolytic anaemia), blood in the urine, weakness and a high heart rate. NC State rates it as having low severity poison characteristics. Keep pets away from bulbs, tops and kitchen trimmings, and call a vet if one eats any.

## Good and bad

**Pros**
- Wide planting window: nursery September–November, field October–December (Ministry)
- Green onions can be pulled from about 60 days (Ministry's shorter harvest time)
- Compact: 10–15 cm spacing suits raised beds and troughs (UF/IFAS)
- Cured bulbs keep in a cool, dry, ventilated place (UF/IFAS)

**Cons**
- Slow: bulbs take about 150 days (Ministry) or 4–5 months (UF/IFAS)
- FAO rates bulb onion salt-sensitive (threshold about 1.2 dS/m)
- Needs short-day cultivars at southern latitudes (UF/IFAS)
- Toxic to dogs, cats and horses if eaten (ASPCA)

## Common mistakes

- Choosing the wrong day-length type. UF/IFAS says short-day cultivars suit southern latitudes, so check the label before buying sets.
- Planting too deep. UF/IFAS says sets go about 2.5 cm below the surface; buried bulbs struggle to swell.
- Letting the bed dry out between waterings. UF/IFAS says to irrigate frequently to keep growth steady.
- Skipping the cure. After lifting, UF/IFAS says bulbs need a couple of weeks in a cool, dark, dry, ventilated place before storage.
- Using salty water. FAO rates bulb onion as sensitive to salt, with a threshold of about 1.2 dS/m.

## Good to know

- The Ministry's calendar lists two harvest times for onion, 150 days and 60 days, which fit bulbs and green onions.
- Khaleej Times reported that the Ministry's Undersecretary named green onion among the crops for home gardens in October 2024.
- Shallots are a botanical variety of the onion, treated as a separate species until 2011 (Wikipedia).
- FAO rates onion grown for seed as moderately sensitive and onion grown for bulbs as sensitive to salt.

## Using it in a garden

Roles: Raised-bed winter crop, Edging row, Trough crop for small gardens, Kitchen staple for a rotation

Give onions a sunny raised bed or a deep trough with sweet soil and compost, close to the kitchen so green onions are pulled as needed. Their narrow tops cast little shade, so they fit between leafy rows or along a bed edge. Keep them away from the salty native sand and from sprinklers, and give them a drip line on a timer.

- [Garlic](https://plantguide.ae/plants/garlic.md): A close relative with the same October to December season, so the two share a bed and a feeding routine.
- [Carrot](https://plantguide.ae/plants/carrot.md): A root crop with the same autumn sowing window, whose narrow tops sit comfortably beside onion rows.
- [Lettuce](https://plantguide.ae/plants/lettuce.md): A quick winter salad crop for the spaces between onion rows, harvested before the bulbs need the room.
- [Cauliflower](https://plantguide.ae/plants/cauliflower.md): A different family on the same calendar, so the two can follow each other in a bed rotation.

## FAQ

**When should I plant onions in Dubai?**  
The Ministry's calendar gives nursery planting from September to November and field planting from October to December.

**How long do onions take to grow?**  
The Ministry lists two harvest times, 150 days and 60 days. UF/IFAS says bulbs are ready in four to five months, when about a quarter of the tops have fallen over.

**Which onion type should I choose?**  
A short-day cultivar. UF/IFAS says onions are short, mid or long day depending on the hours of daylight they need to form a bulb, and southern growers should choose short-day types.

**Should I grow onions from seed or sets?**  
UF/IFAS says you can grow from seed, but sets are quicker and easier and give an earlier harvest.

**Are onions safe for pets?**  
No. The ASPCA lists onion as toxic to dogs, cats and horses, and the signs include vomiting and damage to red blood cells. Keep pets away from the bed and from trimmings.

**How do I store homegrown onions?**  
Cure them for a couple of weeks in a cool, dark, dry, well-ventilated place, trim the tops and roots, and store the bulbs somewhere cool and dry (UF/IFAS).

## Related plants

[Garlic](https://plantguide.ae/plants/garlic.md) · [Chives](https://plantguide.ae/plants/chives.md) · [Carrot](https://plantguide.ae/plants/carrot.md) · [Lettuce](https://plantguide.ae/plants/lettuce.md) · [Cauliflower](https://plantguide.ae/plants/cauliflower.md)

## Photos

![Onions growing in a vegetable garden, with green leaves and bulbs swelling at the soil surface](https://upload.wikimedia.org/wikipedia/commons/4/40/Oignons-FR-2013.jpg)  
Photo: JLPC / CC BY-SA 3.0 / Wikimedia Commons ([source](https://commons.wikimedia.org/wiki/File:Oignons-FR-2013.jpg))

![Red onions lifted from dark soil with their green tops still attached](https://upload.wikimedia.org/wikipedia/commons/4/46/Onion_crop.jpg)  
Photo: Kasyap / CC BY-SA 4.0 / Wikimedia Commons ([source](https://commons.wikimedia.org/wiki/File:Onion_crop.jpg))

![A tray of harvested red and white onions curing with their dry tops still on](https://upload.wikimedia.org/wikipedia/commons/0/0e/Common_onion_harvested_at_Goodnestone_Park_Kent_England.jpg)  
Photo: Acabashi / CC BY-SA 4.0 / Wikimedia Commons ([source](https://commons.wikimedia.org/wiki/File:Common_onion_harvested_at_Goodnestone_Park_Kent_England.jpg))

![Three golden onion bulbs on a pale background](https://upload.wikimedia.org/wikipedia/commons/0/08/Allium_cepa_%282944502550%29.jpg)  
Photo: Alex Lomas / CC BY 2.0 / Wikimedia Commons ([source](https://commons.wikimedia.org/wiki/File:Allium_cepa_(2944502550).jpg))

## Sources

- [UAE Ministry of Climate Change and Environment: Dates for Planting Vegetables and Fruits in the UAE](https://moccae.gov.ae/assets/download/56f7a89b/agriculture_calender_page_en.pdf.aspx)
- [Khaleej Times: UAE to help residents grow their own fruits and vegetables in home gardens](https://www.khaleejtimes.com/uae/environment/uae-to-help-residents-grow-their-own-fruits-vegetables-in-home-gardens)
- [FAO: Crop salt tolerance data (Annex 1)](https://www.fao.org/4/y4263e/y4263e0e.htm)
- [Gulf News: Gardening tales from the UAE, how to grow a kitchen garden on your balcony this summer](https://gulfnews.com/friday/home/gardening-tales-from-the-uae-how-to-grow-a-kitchen-garden-in-your-balcony-this-summer-1.1679993345418)
- [Wikipedia: Climate of Dubai (1991 to 2020 normals)](https://en.wikipedia.org/wiki/Climate_of_Dubai)
- [UF/IFAS Gardening Solutions: Onions and Shallots](https://gardeningsolutions.ifas.ufl.edu/plants/edibles/vegetables/onions/)
- [ASPCA: Onion (Allium cepa)](https://www.aspca.org/pet-care/animal-poison-control/toxic-and-non-toxic-plants/onion)
- [NC State Extension Gardener Plant Toolbox: Allium cepa](https://plants.ces.ncsu.edu/plants/allium-cepa/)
- [Wikipedia: Onion](https://en.wikipedia.org/wiki/Onion)
- [Arabic Wikipedia: بصل](https://ar.wikipedia.org/wiki/%D8%A8%D8%B5%D9%84)
- [Hindi Wikipedia: प्याज](https://hi.wikipedia.org/wiki/%E0%A4%AA%E0%A5%8D%E0%A4%AF%E0%A4%BE%E0%A4%9C)
- [Urdu Wikipedia: پیاز](https://ur.wikipedia.org/wiki/%D9%BE%DB%8C%D8%A7%D8%B2)
- [Malayalam Wikipedia: ഉള്ളി](https://ml.wikipedia.org/wiki/%E0%B4%89%E0%B4%B3%E0%B5%8D%E0%B4%B3%E0%B4%BF)
- [Tamil Wikipedia: வெங்காயம்](https://ta.wikipedia.org/wiki/%E0%AE%B5%E0%AF%86%E0%AE%99%E0%AF%8D%E0%AE%95%E0%AE%BE%E0%AE%AF%E0%AE%AE%E0%AF%8D)
- [Tagalog Wikipedia: Sibuyas](https://tl.wikipedia.org/wiki/Sibuyas)
- [Bengali Wikipedia: পিঁয়াজ](https://bn.wikipedia.org/wiki/%E0%A6%AA%E0%A6%BF%E0%A6%81%E0%A6%AF%E0%A6%BC%E0%A6%BE%E0%A6%9C)
- [Persian Wikipedia: پیاز](https://fa.wikipedia.org/wiki/%D9%BE%DB%8C%D8%A7%D8%B2)