Green onions come from the same species as regular bulb onions, Allium cepa, or in some cases from a closely related species called Allium fistulosum, which originated in central Asia. What you buy in the grocery store labeled “green onions” or “scallions” are simply young onion plants harvested before the bulb has a chance to fully develop. They’ve been cultivated for thousands of years, with origins traced to regions of western China and central Asia, and they now grow on every inhabited continent.
The Plant Behind Green Onions
Green onions aren’t a separate vegetable from regular onions. They’re the same plant at an earlier stage of growth. When an onion seed sprouts, it first produces long, hollow green shoots. If left in the ground long enough, energy from those shoots concentrates into a large bulb underground. Farmers growing green onions simply pull the plant while it’s still young, when the base is narrow and white and the tops are tall and green.
Two species are commonly sold as green onions. The first is the common bulb onion, harvested early. The second is Allium fistulosum, sometimes called the Welsh onion or Japanese bunching onion, which naturally never forms a large bulb. This species stays slender even at maturity, making it ideal for year-round green onion production. Most of the green onions you find in Asian grocery stores come from this bunching variety, while Western supermarkets sell a mix of both.
Geographic Origins and Spread
The oldest evidence of onion cultivation points to central and western Asia, particularly the area around modern-day Iran, Pakistan, and western China. Allium fistulosum specifically is native to northwestern China and Siberia, where it has been grown for at least 2,000 years. From there, it spread east to Japan and Korea, where it became a cornerstone of cooking traditions.
Onions of all types moved westward through trade routes into the Middle East, Egypt, and eventually Europe. By the time Spanish and Portuguese explorers reached the Americas, they brought onion seeds with them. Today, green onions are grown commercially in Mexico, the United States, China, Japan, and across Southeast Asia. Mexico is the primary supplier for the U.S. market, with significant domestic production in California, Arizona, and Texas.
How Green Onions Are Grown
Green onions are one of the simplest crops to produce. They can be grown from seed or from small bulb sets planted directly in soil. In commercial farming, seeds are sown densely in rows, and the plants are harvested 60 to 80 days later, depending on the variety and climate. Because they don’t need time to form a bulb, their growing season is much shorter than that of storage onions, which can take four to five months.
They prefer cool to mild weather and grow well in temperatures between 55°F and 75°F, though they tolerate light frost. In warmer climates like southern California and northern Mexico, farmers can plant and harvest green onions year-round by staggering planting dates every few weeks. This is why green onions are available in stores every month of the year, unlike many seasonal vegetables.
Home gardeners can regrow green onions from kitchen scraps by placing the root end in a glass of water on a windowsill. The shoots will regrow within a week, though the flavor becomes milder with each cutting. Planting the root end in soil produces stronger, more flavorful regrowth.
Green Onions vs. Scallions vs. Spring Onions
The terminology around green onions causes real confusion, and it varies by region. In the United States, “green onions” and “scallions” mean the same thing: a young, slender onion with no significant bulb at the base. The terms are interchangeable at the grocery store.
“Spring onions” are different. These are onions pulled slightly later in growth, after a small round bulb has started to form at the base. The bulb is usually marble-sized or a bit larger, with a stronger, more pungent flavor than a true scallion. Spring onions are more common in British and Australian cooking, and you’ll sometimes find them at farmers’ markets in the U.S.
Chives, while they look similar, are a completely different species (Allium schoenoprasum). They’re much thinner, more delicate in flavor, and used as an herb rather than a vegetable.
Nutritional Profile
Green onions are low in calories, with a typical serving of three or four stalks containing about 10 calories. Their green tops are the more nutritious part, providing vitamin K (important for blood clotting and bone health), vitamin C, and vitamin A in the form of beta-carotene. The white base contains more of the sulfur compounds that give onions their sharp taste and that are linked to anti-inflammatory effects.
One cup of chopped green onions delivers roughly 100% of your daily vitamin K needs and about 20% of your vitamin C. They also provide folate and small amounts of calcium and iron. Because you typically eat them raw or lightly cooked, the heat-sensitive nutrients stay mostly intact.
How They’re Used Around the World
Green onions play different roles depending on the cuisine. In Chinese cooking, they’re one of the foundational aromatics alongside ginger and garlic, used in stir-fries, dumpling fillings, and scallion pancakes. Korean cuisine uses them extensively in kimchi, pajeon (scallion pancakes), and as a garnish for soups and stews. Japanese cooking features them finely sliced over ramen, tofu, and grilled meats.
In Mexican cuisine, green onions are charred whole on a grill alongside carne asada, served as a smoky, sweet side. American and European cooking tends to use them raw as a garnish for baked potatoes, salads, and dips. They’re mild enough to eat without cooking but flavorful enough to stand on their own when grilled or roasted.
Both the white and green parts are edible. The white base has a sharper, more onion-forward bite, while the green tops taste milder and slightly grassy. Recipes that call for green onions often specify which part to use, but in most cases, the entire stalk works.