Green Onions — Cups to Grams

Green Onions, Scallions, and Spring Onions: Are They the Same?

In American English, "green onions" and "scallions" refer to the same vegetable — young onion plants harvested before the bulb has formed, with long green hollow tops and a small white base. "Spring onions" in British and Australian English can mean the same thing, though sometimes it refers to a slightly more mature plant with a more developed round bulb at the base.

The botanical distinction that matters in the kitchen: true scallions (Allium fistulosum, Welsh onion or bunching onion) never form a bulb and remain straight-based throughout their life. What Americans call "green onions" from the supermarket are often young Allium cepa (standard bulb onion) harvested early, and these will have a slightly rounded base. The flavor and kitchen usage are identical — the botanical distinction is academic for cooking purposes.

What is most important for recipe interpretation: when a recipe says "3 green onions, thinly sliced," it means approximately 3–4 tablespoons (approximately 25–30g) of chopped scallion. When it says "½ cup chopped green onions," it means approximately 25g. When it says "1 bunch" without specifying cups, expect 1 cup or approximately 50g from a standard grocery bunch of 5–7 stems.

White Parts vs Green Parts: Two Different Ingredients

Separating the white and green parts of scallions is standard practice in professional kitchens, treating each part as a functionally distinct ingredient. The flavor chemistry drives this separation: the white and light-green base sections contain higher concentrations of organosulfur compounds (allicin precursors) that are pungent raw but sweeten and mellow with heat. The dark green tops contain chlorophyll that gives them a fresh, sharp flavor but deteriorates rapidly with heat.

White parts (stem and pale green base): Add to hot oil at the beginning of cooking — stir-fry applications typically sauté white scallion parts for 30–60 seconds to bloom their flavor before adding other ingredients. In soups and stews, add with the aromatics (onion, garlic stage). In compound butters, they can be used raw but their sharpness is more pronounced. Weight per cup: 48g (denser than green parts).

Green parts (dark green hollow tops): Add at the very end of cooking or use raw as garnish. They wilt from bright to olive-drab green within 30–60 seconds of heat exposure. In stir-fries, they go in during the final 30 seconds of wok cooking. As a soup garnish, add to individual bowls immediately before serving. In dressings and cold dishes, they can be used raw throughout. Their bright color is their primary visual value — heat destroys it.

Scallions in Specific Recipe Applications

Scallion pancakes (cong you bing): One of the most iconic Chinese street foods, relying on a specific quantity of green onions to achieve the characteristic laminated-onion structure. Standard recipe for 4 pancakes: 300g hot water dough (300g all-purpose flour + 170ml just-boiled water), 1 cup (50g) chopped green onions (green parts preferred for color), 3 tablespoons sesame oil, and 1 teaspoon fine salt. The scallions are scattered across the sesame-oiled dough, the dough is rolled into a log, the log coiled, pressed flat, and pan-fried 3–4 minutes per side in 2 tablespoons neutral oil.

Korean pajeon (scallion pancake): Distinct from Chinese scallion pancakes — thinner, more eggy, and uses whole scallion sections rather than chopped. A 4-portion batch uses 1 bunch (50g) green onions, left in 10–12cm lengths and laid flat in a batter of 1 cup flour, 1 cup water, 2 eggs, and salt. The scallions are the visual structure of the pancake, visible through the thin batter. The entire pancake should be one continuous piece with scallion sections arranged parallel across it.

Baked potato topping: The classic American loaded baked potato uses 2–3 tablespoons (6–9g) of thinly sliced scallion green tops as one of four key toppings (with sour cream, cheddar, and bacon). The green tops provide color contrast and fresh onion flavor that cuts through the richness of the other toppings.

French onion soup: Unlike the name suggests, this does not use scallions — it uses mature sliced yellow onions. However, French vichyssoise (cold leek and potato soup) is sometimes garnished with 2 tablespoons (6g) of thinly sliced scallion greens per bowl. The cold soup amplifies the sharp scallion flavor, so use the minimum recommended amount.

Green Onion Storage: Keep Them Fresh for 3 Weeks

Green onions are one of the easiest vegetables to keep fresh — or to regrow — with the right storage method. They deteriorate quickly (3–5 days) in the wrong conditions and stay vibrant for 2–3 weeks with simple correct storage.

The water-jar method (best results): Do not wash. Trim just the root-end fuzzy fibers but leave the white base intact (cutting off roots kills the plant). Place bundle root-end down in a jar or tall glass with 1–2 inches of water. Cover the green tops loosely with a plastic bag. Refrigerate. Change the water every 3–4 days. The plants continue to grow in the refrigerator — green tops elongate 1–2cm per week — and the roots develop further. With this method, green onions remain crisp and usable for 3 weeks or longer. A bonus: the white bases can be rinsed and replanted in a pot of soil if you want an ongoing supply.

Paper towel method (simpler but shorter life): Do not wash. Wrap the bunch in a slightly damp (not wet) paper towel, then place in a zip-lock bag. Do not seal completely — leave a small air gap. Refrigerate. Lasts 1–2 weeks. Check the paper towel every few days and replace if it becomes soggy or slimy.

Avoid: storing already-cut scallions in an airtight container without absorbency — they turn slimy within 2–3 days. Never store cut scallions near strongly aromatic foods (butter, soft cheeses) in the refrigerator — the volatile sulfur compounds transfer and affect the flavor of neighboring ingredients.

Green Onions Conversion Table

Common Questions About Green Onions

• How many grams in 1 cup of chopped green onions?

  1 cup chopped green onions (both white and green parts) = 50 grams. Thinly sliced = 52g. White parts only = 48g. Green tops only ≈ 32g. 1 standard grocery bunch (5–7 stems) = approximately 1 cup chopped. When precision matters, weigh — the hollow green tops create significant air space that makes cup measurements variable.

• How many green onions make 1 cup?

  Approximately 5–6 medium scallions make 1 cup chopped (50g), using both green and white parts. Each medium scallion weighs 15–20g whole and yields 2–3 tablespoons (7–10g) chopped. A standard grocery bunch contains 5–7 stems and typically yields close to 1 cup. Size varies significantly between bunches — weighing is more reliable than counting stems.

• What is the difference between white and green parts of scallions?

  White/pale-green base: more pungent, holds up to heat, add at the beginning of cooking to bloom flavor. Dark green tops: fresh and sharp raw, bright in color, lose color and flavor quickly when heated — add in the final 30 seconds or use raw as garnish. In stir-fries, wok the white parts first, add green tops at the very end. For soup garnish, use green tops only, added to individual bowls right before serving.

• How do I keep green onions fresh longer?

  Root-end down in a jar with 1–2 inches of water, cover loosely with a plastic bag, refrigerate. Change water every 3–4 days. Scallions stay fresh 2–3 weeks this way and the green tops continue to grow. Bonus: the white bases can be replanted in soil for a continuing supply. The paper towel wrap method (damp towel, zip-lock bag) works for 1–2 weeks but dries out faster.

• Can I substitute chives for green onions?

  Chives substitute for the green tops of scallions at equal weight — they are thinner and milder but deliver similar fresh onion flavor and color in garnish applications. Chives cannot substitute for the white parts of scallions in cooked applications — chives have no firm base and turn soft immediately. For cooked recipes requiring the white parts, substitute shallots (use ½ the weight) or leeks (equal weight) for better results.

• How much green onion for scallion pancakes?

  Chinese cong you bing: 1 cup (50g) chopped green onions (green parts preferred for color) per batch of 4 pancakes made with 300g flour dough. Korean pajeon: 1 bunch (50g) left in long sections, laid flat in batter, for 2 large pancakes (serves 4). Both use the full scallion quantity as the primary filling/visual element, not just a garnish.

Related Cooking Converters