Green onions, also called scallions, spring onions or bunching onions, are one of the fastest, easiest and most versatile crops for any grower. From a windowsill jar in a New York apartment to a market garden in Lagos, the same simple principles apply. This guide covers how to grow green onions in 2026, whether you want a permanent kitchen supply from regrown scraps or a small commercial patch that turns over every 60 days.
1. What exactly is a « green onion »?
The name covers three closely related things:
- True bunching onions (Allium fistulosum): perennial, do not form a real bulb. Best for continuous cutting.
- Young common onions (Allium cepa): harvested early before they bulb, sold as spring onions.
- Shallot regrowth and welsh onions: minor variations sold under the same umbrella.
In markets around the world, all three end up in the same bunch. For growers, the practical choice is between bunching onions (grow, cut, regrow, season after season) and seedling onions (pull whole, replant).
2. When to plant
Temperate climate
- Spring sowing: as soon as the soil can be worked, from March to May in the northern US and Europe.
- Fall sowing: from August to September for overwintering harvest early the following spring.
- Green onions tolerate light frost, ideal shoulder-season crop.
Subtropical and tropical climate
- Sow year-round in most zones. Avoid the hottest months in Sahelian regions (over 35 °C soil temperature slows germination sharply).
- In sub-Saharan Africa, the cool dry season (October to February) gives the highest quality bunches with less bolting pressure.
3. Prepare the bed
- Soil: loose, sandy loam. Avoid heavy clay.
- pH: 6.0 to 7.0.
- Sun exposure: at least 6 hours of direct light per day. Tolerates light shade.
- Fertility: work in 3 to 5 cm of well-rotted compost. Green onions are heavier nitrogen feeders than bulb onions.
4. Three ways to start
Option 1, From seed
- Sow directly outdoors at 0.5 to 1 cm depth, thinly along a shallow furrow.
- Spacing: 1 to 2 cm between seeds within the row, 10 to 15 cm between rows.
- Germination: 7 to 14 days at 15–25 °C.
- Thin to 2 to 3 cm apart once seedlings are established.
- Ready to harvest: 60 to 80 days.
Option 2, From sets or seedlings
Small onion sets or nursery-raised seedlings transplant well, cutting weeks off the calendar. Bury the white base 2 cm deep, 5 cm apart.
Option 3, Regrow from kitchen scraps
- Save the white root end of store-bought green onions (about 3 cm long, with roots intact).
- Place root-down in a small glass with just enough water to cover the roots (not the whole stem).
- Place in bright indirect light. Change water every 2 to 3 days.
- Fresh green tops regrow in 5 to 10 days.
- After 2 to 3 rounds of cutting, transplant into soil for continued vigor, the plant depletes without nutrients.
5. Care during growth
Watering
Green onions need consistent, light watering. About 20 to 25 mm per week during active growth. Avoid drought stress, it triggers early bolting and toughens the leaves. Avoid waterlogging, it invites rot.
Feeding
Two light nitrogen applications spaced 3 weeks apart give the best leaf color and flavor. Blood meal, feather meal, or a balanced 10-10-10 at 100 to 150 kg per hectare works well. For home growers, a diluted fish emulsion or seaweed spray every 10 days is fine.
Weeding
Keep the bed weed-free for the first 4 to 5 weeks. After that, the closed canopy of leaves suppresses most competitors.
Pests and diseases
- Onion thrips: silvery streaks on leaves. Treat with insecticidal soap or neem oil if pressure is severe.
- Downy mildew: white to grey fuzz on leaves in humid conditions. Prevent with adequate spacing and morning watering only.
- Pink root: soil-borne fungus. Rotate crops with non-alliums.
Overall, green onions are one of the least pest-prone crops you can grow.
6. Harvest
For bunching onions
- Cut leaves 2 to 3 cm above the soil with clean scissors once they reach 15 to 25 cm. New leaves regrow in 10 to 20 days.
- A single stand can be cut 3 to 5 times before flavor and vigor decline.
For young common onions (spring onions)
- Pull the whole plant when the white base reaches pencil thickness, typically 60 to 80 days from seed.
- Loosen the soil first to avoid breaking stems.
7. Storage and preservation
- Fresh green onions keep for 1 to 2 weeks refrigerated, ideally standing root-down in a jar with 2 cm of water and a loose plastic bag over the top.
- For long-term storage: chop and freeze in ice cube trays with a little water, or dehydrate at 45 °C until brittle and grind into flakes.
8. Yield and commercial potential
- Home garden: a 2 m² bed sown thickly gives a family a steady supply for months.
- Market garden: green onions turn a bed over every 60 to 80 days. Cycle yield: 3 to 5 kg per m² fresh weight, times 4 to 5 harvests per year, one of the highest turnover rates in vegetable production.
- Market price: green onions consistently sell at 4 to 8 times the weight-based price of dry bulb onions because of their perishability and processing labor.
Green onions are an ideal « gateway crop » for market gardeners entering the fresh produce trade. For those planning a market gardening operation, our greenhouse and protected culture and agricultural consulting teams design production layouts that maximize turnover per square meter.
Article by the Jogoo Agriculture agronomy team. Recommendations should be adapted to your climate, variety and locally registered inputs.
Frequently asked questions
How long does it take to grow green onions from seed?
Green onions take 60 to 80 days from seed to first harvest, depending on climate and variety. Bunching onion varieties can then be cut repeatedly, with new leaves regrowing in 10 to 20 days after each cut. A single planting typically supports 3 to 5 cuttings before vigor declines.
Can you grow green onions from kitchen scraps?
Yes. Save the white root end (about 3 cm long with roots intact), place root-down in a glass with enough water to cover just the roots, and set in bright indirect light. Change water every 2 to 3 days. Fresh green tops regrow in 5 to 10 days. After 2 to 3 rounds of cutting, transplant into soil for continued vigor.
Do green onions come back every year?
True bunching onions (Allium fistulosum) are perennial and regrow year after year when their base is left in the soil. Young common onions (Allium cepa) sold as spring onions are annuals, they are pulled whole and replanted. Most commercial « green onions » are a mix of both depending on the region.
What is the difference between green onions, scallions and spring onions?
The three names refer to essentially the same product at slightly different stages. In North America, « green onion » and « scallion » are used interchangeably. In the UK and Australia, « spring onion » is the more common term. Botanically the crop can be either a true bunching onion (Allium fistulosum, no bulb) or a common onion (Allium cepa) harvested young.
How much sunlight do green onions need?
Green onions need at least 6 hours of direct sunlight per day for best growth, though they tolerate light shade. In hot tropical climates, some afternoon shade during peak dry season protects leaf quality and slows bolting.