How long does it take to grow green onions

Green onions, also called scallions or bunching onions, are one of the fastest crops you can grow. From seed, they are ready to harvest in 50 to 60 days, but you can start pulling them as soon as they reach pencil thickness, often around 30 days. If you plant sets (small bulbs), you can harvest in as little as 2 to 3 weeks. The exact time depends on variety, season, and how you plant. Here is the breakdown and how to get a steady supply all season.

From seed: 50 to 60 days to full size

Sow seeds directly in the garden 4 to 6 weeks before your last spring frost, or as soon as the soil can be worked. In USDA zones 3 to 6, that is typically March to April. In zones 7 to 10, you can plant in fall for winter harvests. Seeds germinate in 7 to 14 days at soil temperatures between 50°F and 75°F.

For full-sized green onions with a white shank of 4 to 6 inches, expect 50 to 60 days from sowing. But you do not have to wait that long. Start harvesting when the tops are 6 to 8 inches tall, which can be as early as 30 days. The flavor is milder at this stage, perfect for salads.

Seed spacing and depth

Sow seeds 1/4 inch deep, 1/2 inch apart in rows 12 inches apart. If you want larger stalks, thin to 1 inch apart once seedlings are 2 inches tall. Thinnings are edible, s o use them in the kitchen. For a continuous harvest, sow a new batch every 2 to 3 weeks from early spring to late summer.

From sets: 2 to 3 weeks

Sets are small, dormant bulbs that are easy to plant and speed up the process. Plant sets 1 inch deep, 2 inches apart, in rows 12 inches apart. They will sprout within a week and be ready to pull as green onions in 2 to 3 weeks. This is the fastest method, but sets cost more than seeds. A 1-pound bag of sets costs $8 to $12 and covers about 50 feet of row.

For green onions, choose varieties labeled as bunching or scallion types. ‘White Spear’ and ‘Evergreen Hardy White’ are reliable. If you use regular onion sets, you can harvest them early, but they will form bulbs if left longer.

Varieties that perform best

Not all onions are equal for green onion production. Bunching onions (Allium fistulosum) never form bulbs and are the classic scallion. They are perennial in zones 6 to 10 and can be divided. Good varieties include ‘Tokyo Long White’, ‘Red Beard’, and ‘Nabechan’. These are ready in 50 to 60 days from seed.

Regular bulb onions (Allium cepa) can also be harvested as green onions. Use varieties like ‘White Lisbon’ or ‘Walla Walla’ if you want the option to let some mature into bulbs. They are slightly faster, around 45 to 55 days.

Quick comparison table

Method	Time to harvest	Cost	Notes
Seeds	50-60 days	$2-$4 per packet	Best for large quantities
Sets	2-3 weeks	$8-$12 per pound	Fastest, but costlier
Transplants	3-4 weeks	$3-$5 per 6-pack	Good for early start

How to speed up growth

Green onions grow fastest in cool weather (60°F to 70°F) with consistent moisture. Here are three tips to shave a few days off the clock:

1. Soak seeds overnight before planting. This can cut germination time by 2 to 3 days.
2. Use a floating row cover in early spring to keep soil warm and protect from pests. This can add 5 to 10 days of growth.
3. Fertilize with a high-nitrogen feed (like blood meal or fish emulsion) at half strength every 2 weeks. Nitrogen pushes leafy growth, which is what you harvest.

Avoid overwatering, which can cause rot. Keep the soil evenly moist, not soggy.

Harvesting and regrowth

You can harvest green onions two ways. Pull the whole plant when it reaches 6 to 8 inches tall, or cut the tops at 2 inches above the soil and let them regrow. The cut method works best for bunching onions. You can get 2 to 3 cuts per planting, but each regrowth is slower and thinner. For a continuous supply, plant a new patch every 3 weeks.

To store, keep unwashed green onions in a plastic bag in the fridge. They last 1 to 2 weeks. You can also chop and freeze them, but they will lose crispness.

Common problems and fixes

• Bolting (flowering): If temperatures drop below 40°F for a week or more, plants may bolt. Use bolt-resistant varieties like ‘Evergreen Hardy White’.
• Thrips: These tiny insects cause white streaks on leaves. Spray with insecticidal soap or neem oil. A floating row cover prevents them.
• Poor germination: Seeds need light to germinate, so do not bury them too deep. Keep the soil moist until sprouts appear.

FAQ

Can I grow green onions indoors? Yes, you can grow them in a sunny windowsill or under a grow light. Use a 6-inch pot with drainage, plant seeds 1/4 inch deep, and harvest in 50 to 60 days. For faster results, plant sets and harvest in 3 weeks. Indoor growth is slower in winter due to lower light.

How long do green onions last after harvest? In the fridge, unwashed green onions last 1 to 2 weeks. Wrap them in a damp paper towel and put them in a plastic bag. You can also stand them in a glass of water with the roots submerged; they will stay fresh for a few days and may regrow.

Can I regrow green onions from kitchen scraps? Yes, place the white root ends in a glass of water, covering the roots. Change water every 2 days. New shoots appear in 3 to 5 days. You can harvest in 2 weeks, but the regrowth is less vigorous than from seed. After 2 cycles, plant them in soil for better results.

What is the best time to plant green onions? In cool climates, plant as soon as the soil is workable in early spring. In warm climates (zones 8+), plant in fall for winter harvest. You can succession plant every 2 to 3 weeks until late summer for a continuous supply.

The bottom line

Green onions are one of the quickest crops you can grow. From seed, expect 50 to 60 days to full size, but you can start harvesting in 30 days. From sets, you can harvest in 2 to 3 weeks. Choose bunching varieties for the best scallions, plant in cool weather, and succession sow for a steady supply. With minimal effort, you will have fresh green onions from spring through fall.